Damage Calculations

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Battle Opening  · Artillery Spotting  · Anti-Submarine Warfare Cut-In
Support Expedition  · Special Attacks  · Anti-Installation  · Friendly Fleet  · Drop
Map Mechanics and Nodes  · Evacuation  · Damage Calculations  · Accuracy, Evasion and Criticals  · Shooting Order and Targeting

The main goal of the game is to sink Abyssals. Abyssals are sunk by doing Damage to them. This page lists all the applicable formulas and mechanics that affect the calculation of Damage.

Please note that all formulas between [math]\displaystyle{ \lfloor \ \rfloor }[/math] or marked with [math]\displaystyle{ \downarrow }[/math] are rounded down.

  • For example, [math]\displaystyle{ \lfloor 4.2 \rfloor = 4 }[/math].
  • [math]\displaystyle{ 4.2 \times_\downarrow 1.5 = \lfloor 4.2 \times 1.5 \rfloor = \lfloor 6.3 \rfloor = 6 }[/math], but [math]\displaystyle{ 4.2 \times_\downarrow 1 = 4.2 }[/math] (by definition, [math]\displaystyle{ \times_\downarrow }[/math] is then a non-commutative non-associative operator, it is assumed to be left-associative with lower priority than the usual multiplication operator).
    • [math]\displaystyle{ \times_\downarrow }[/math] is used when the round down applies only when the modifier is applied.


Damage Formula

The Damage is the reduction of HP   caused by an attack hitting a target. The formula is the same for all attacks as well as abyssals. It stems from the difference between the final attack power of the assailant and the defense power of the target.

Damage Formula
[math]\displaystyle{ \text{Damage} = \biggl \lfloor \biggl ( \text{Atk}_\text{post-cap} - \text{DEF} \biggr ) \times \text{Ammo} \biggr \rfloor }[/math]
With
  • [math]\displaystyle{ \text{Atk}_\text{post-cap} }[/math] the final attack power of the assailant after the cap and all the modifiers have been applied, described below,
  • [math]\displaystyle{ \text{DEF} }[/math] the defensive power of the target,
  • [math]\displaystyle{ \text{Ammo} }[/math] the remaining ammunition modifier.
Notes
  • If [math]\displaystyle{ \text{Atk}_\text{post-cap} }[/math] is inferior to [math]\displaystyle{ \text{DEF} }[/math] or if [math]\displaystyle{ \text{Ammo}=0 }[/math] then the attacks will deal "scratch damage".

Defense Power

Defense power represents the ability of a ship to resist damage. It's calculated from the Armor   plus a random element.

Defense Formula
[math]\displaystyle{ \text{DEF} = \left( \text{Armor} \times 0.7 + \text{Armor}_\text{rand} \times 0.6 \right) - \text{Pen} }[/math]
With
  • [math]\displaystyle{ \text{Armor} }[/math] the armor   of the target including all equipment and upgrade bonuses,
    • This stat is be directly affected by Debuffs when applicable.
  • [math]\displaystyle{ \text{Armor}_\text{rand} }[/math] a random number between [math]\displaystyle{ 0 }[/math] and [math]\displaystyle{ \lfloor\text{Armor}\rfloor - 1 }[/math],
    • Note that it is inclusive, meaning it can also output [math]\displaystyle{ 0 }[/math] and [math]\displaystyle{ \lfloor\text{Armor}\rfloor - 1 }[/math]
  • [math]\displaystyle{ \text{Pen} }[/math] any applicable armor penetration mechanic:
    • See ASW for details on ASW armor penetration,
Notes
  • The range of armor values is uniformly distributed, every armor roll has the same chance of occurring.

For short, defensive power randomly varies between 1.3 x  and 0.7 x .

Attacks Power

Attack power represents the ability of a ship to inflict damage. It's affected by a lot of different elements (stats, mechanics, "battle state", etc.) through 4 steps of calcul:

  1. Basic
    • Generally calculated from the relevant stats of the ship using different formulas according to the type of attack and the phase of battle
  2. Pre-cap
    • The basic attack goes through different modifiers
  3. Cap
    • If the attack is superior to a cap it's reduced
  4. Post-cap
    • These modifiers are more potent because they are not limited by the cap
Attack Step Formulas
Pre-cap
[math]\displaystyle{ \text{Atk}_\text{pre-cap} = \text{Atk}_\text{base} \times \text{Mod}_\text{pre-cap} }[/math]
With
  • [math]\displaystyle{ \text{Atk}_\text{base} }[/math] is the basic attack power of the relevant attack.
  • [math]\displaystyle{ \text{Mod}_\text{pre} }[/math] is any pre-cap modifiers that are applicable.
Cap

The attack is then capped as follows:

[math]\displaystyle{ \text{Atk}_\text{cap} = \text{Cap} + \sqrt{\text{Atk}_\text{pre-cap} - \text{Cap}} }[/math]
With
  • [math]\displaystyle{ \text{Cap} }[/math] is the damage cap relevant to the phase.
[math]\displaystyle{ Cap }[/math]
Attack Type Cap
Support Expeditions 170
ASW
Airstrike
Opening Torpedo Salvo 180
Closing Torpedo Salvo
LBAS 220 [1]
Day shelling
Night battle 360
Post-cap

Capped attack is then modified by post-cap modifiers:

[math]\displaystyle{ \text{Atk}_\text{post-cap} = \lfloor \text{Atk}_\text{cap} \rfloor \times \text{Mod}_\text{spotting} \times \text{Mod}_\text{CVCI} \times \text{Mod}_\text{balloon S} \times_\downarrow \text{Mod}_\text{AP} \times \text{Mod}_\text{post} \times \text{Mod}_\text{balloon N} \times_\downarrow \text{Crit} }[/math]
With
  • [math]\displaystyle{ \text{Atk}_\text{cap} }[/math] the Cap Adjusted Attack Power,
  • [math]\displaystyle{ \text{Mod}_\text{spotting} }[/math] the bonus from artillery spotting,
  • [math]\displaystyle{ \text{Mod}_\text{CVCI} }[/math] the bonus from carrier cut-ins,
  • [math]\displaystyle{ \text{Mod}_\text{AP} }[/math] the bonus from AP shells,
    • The value is rounded down after applying [math]\displaystyle{ \text{Mod}_\text{AP} }[/math] only if the target is able to take extra damage from AP shells, even if [math]\displaystyle{ \text{Mod}_\text{AP} }[/math] is 1 due to the attacker not having AP shells.
  • [math]\displaystyle{ \text{Mod}_\text{balloon} }[/math] the bonus from barrage balloons. The position of the modifier in the formula depend of the type of attack:
    • [math]\displaystyle{ \text{Mod}_\text{balloon S} }[/math] is the position for artillery spotting, CVCI and special attacks,
    • [math]\displaystyle{ \text{Mod}_\text{balloon N} }[/math] is the position for normal attacks.
  • [math]\displaystyle{ \text{Mod}_\text{post} }[/math] any remaining post-cap modifiers that are applicable,
  • [math]\displaystyle{ \text{Crit} }[/math] the critical modifier,
    • The value is rounded down after applying [math]\displaystyle{ \text{Crit} }[/math] only if the attack is critical.

Basic Attack Power Formulas

The following section details the different formulas to calculate [math]\displaystyle{ \text{Atk}_\text{base} }[/math]. As the formula depends on the type of attacks and the combat phase.

Below are the common variables used in all accuracy formulas:

  • [math]\displaystyle{ \text{FP} }[/math] is the Firepower   of the ship including equipment.
  • [math]\displaystyle{ \text{TP} }[/math] is the Torpedo   of the ship including equipment or the torpedo of a plane.
  • [math]\displaystyle{ \text{ASW} }[/math] is the Anti-submarine   of the ship or equipment.
  • [math]\displaystyle{ \text{DB} }[/math] is the Dive bombing   of the plane.
  • [math]\displaystyle{ \bigstar }[/math] is the upgrade bonus of the equipment.
  • [math]\displaystyle{ \text{Count}_\text{Plane} }[/math] is the remaining amount of planes in a slot, performing the attack.
  • [math]\displaystyle{ \text{Mod}_\text{CF} }[/math] is the combined fleet modifier based on the tables below:

Combat Phase Forces Carrier Task Force Surface Task Force Transport Escort Force
Main Fleet Shelling Allies +2 +10 -5
Enemy +10 +5 +10
Escort Fleet Shelling Allies +10 -5 +10
Enemy +5 -5 +5
Torpedo Allies -5 -5 -5
Enemy -5 -5 -5

Combat Phase Forces Carrier Task Force Surface Task Force Transport Escort Force
Main Fleet Shelling Allies +2 +2 -5
Enemy +10 +10 +10
Escort Fleet Shelling Allies -5 -5 -5
Enemy -5 -5 -5
Torpedo Allies +10 +10 +10
Enemy +10 +10 +10

Combat Phase Forces Bonus
Vs Main Fleet Allies +5
Enemy +10
Vs Escort Allies +5
Enemy -5
Torpedo Allies +10
Enemy +10

Airstrike

The damage from airstrikes is calculated independently for each plane slot and mainly depends on the stats of the plane and the current plane count of the slot.

Airstrike Attack Formula
[math]\displaystyle{ \text{Atk}_\text{base airstrike} = \text{Type} \times \biggl( \left( \text{DB or TP} + \bigstar \right) \times \sqrt{\text{Count}_\text{Plane} } + 25 \biggr) }[/math]
With
  • [math]\displaystyle{ \text{Type} }[/math] is a multiplier based on the type of the plane. See below for details.
[math]\displaystyle{ \text{Type} }[/math]
Plane Type Multiplier Notes
  Torpedo Bombers 0.8x or 1.5x The multiplier is chosen randomly.
The chance is roughly 50%.
 
 Bomber
 Hayabusa
Dive Bombers
Seaplane Bombers
ASW Hayabusa 
 
1.0x  Hayabusa ASW Hayabusa 
 
's  
is counted as 0.
 
 
Jets
(During jet assault)
1.0x
Jets
(During normal bombing)
0.7071x
Notes
  • Airstrike power is calculated independently for each equipment slot on the carrier.
  • The firepower of the carrier does not affect airstrike power.
  • The power is calculated after the air combat and anti-air fire phases which means bombers getting shot down will affect the final calculation.
  • It is not affected by engagement, formation or damage states.
  • It is affected by contact.

This applies to Jet Assaults and Airstrikes.

Surface Shelling

The surface shelling damage stems directly from the Firepower   of the ship.

Surface Attack Formula
[math]\displaystyle{ \text{Atk}_\text{base shelling} = \text{FP} + \bigstar + \text{Mod}_\text{CF} + 5 }[/math]
Notes
  • The caliber of the gun does not affect damage.
  • Abyssal installations that are not equipped with a plane that has a torpedo or dive bombing stat will use the surface shelling formula for calculating damage.

This applies to most ships during the Shelling phase (unless it is an ASW attack).

Carrier Shelling Attacks

Unlike during airstrikes, carrier shelling does not depend on the plane slot and instead combines the stat of the carrier and all planes equipped to one attack.

Carrier Shelling Attack Formula
[math]\displaystyle{ \text{Atk}_\text{base carrier shelling} = \bigl\lfloor \left( \text{FP} + \text{TP} + \bigstar + \left[ \text{DB} \times 1.3 \right] + \text{Mod}_\text{CF} \right) \times 1.5 \bigr\rfloor + 55 }[/math]
Notes
  • Dive and Torpedo groups contribute, respectively, 1.95 and 1.5 times their dive bomb and torpedo stats toward shelling power
  • [math]\displaystyle{ TP }[/math] is the sum of all   torpedo stat any equipment including Fit Bonus.
  • [math]\displaystyle{ DB }[/math] is the sum of all   bombing stat any equipment including Fit Bonus.
  • If a carrier is not equipped with any   torpedo or   dive bombers, she will not participate in shelling.
    • This also applies if they have lost all bombers during the aerial combat phase.
    • But even if an air group has had all its planes shot down, it will still contribute towards carrier shelling power (if the CV is still capable of attacking).
  • Remember that there are potentially multiple sources of [math]\displaystyle{ \bigstar }[/math] bonuses.
  • Slot sizes and the number of remaining aircraft do not affect carrier attack power during shelling.
  • Carriers have the easiest time hitting the damage cap. This makes them very powerful assets for the fleet.
  • Abyssal installations equipped with a plane that has a torpedo or dive bombing stat will use the carrier formula for determining shelling damage.
  • Planes are not shot down when a carrier participates in shelling.

This applies to carriers during the Shelling phase (unless it is an ASW attack).

Torpedo Attacks

Torpedo damage stems directly from the Torpedo   of the ship.

Torpedo Attack Formula
[math]\displaystyle{ \text{Atk}_\text{base torpedo} = \text{TP} + \bigstar + \text{Mod}_\text{CF} + 5 }[/math]
Notes
  • Torpedoes cannot target submarines and Abyssal installations.
    • If the only available targets are submarines, the attack will trigger but always miss.
    • If the only available targets are installations, the attack will not trigger.
  • A ship must have a base torpedo stat of more than 0 to perform torpedo attacks.

Torpedo Attacks only include the Opening Torpedo Salvo and Closing Torpedo Salvo.

Anti-Submarine Warfare

The stats used to calculate damage against submarines is the   ASW.

  • When contributing to ASW power, Base   ASW is square rooted, while equipment ASW is multiplied by 1.5.
    • Anti-submarine weaponry is therefore the primary source of ASW damage, with the base ship ASW playing a very minor role damage-wise.
    • However, base ship ASW is the primary determinant of whether a ship can reach 100 total ASW to perform "Opening ASW" (OASW) attacks.
  • Unlike shelling, ASW damage is capped at 170.

ASW attacks have different modifiers gained from Formations,

Anti-Submarine Formula
[math]\displaystyle{ \text{Atk}_\text{base ASW} = \left( 2\sqrt{\text{ASW}_\text{ship} } + 1.5 \times \bigg[ \sum_\text{All Equipment} (\text{ASW}_\text{equip} + \uparrow \text{ASW}_\text{fit bonus} ) \bigg] + \bigstar + \text{Type}_\text{ship} \right) \times \text{Mod}_\text{synergy} }[/math]
With
  • [math]\displaystyle{ \text{ASW}_\text{equip} }[/math] is the   stat of anti-submarine equipment and attack planes.
  • [math]\displaystyle{ \uparrow \text{ASW}_\text{fit bonus} }[/math] unlike [math]\displaystyle{ \text{ASW}_\text{equip} }[/math] this is the   from Fit Bonuses of all equipment.
  • [math]\displaystyle{ \text{Type}_\text{ship} }[/math] a constant depending on the type of the ship performing the attack. See below for details.
Ship Type Constant
Ship Types [math]\displaystyle{ \text{Type}_\text{ship} }[/math]
Coastal Defense Ships (DE)
Destroyers (DD)
Light Cruisers (CL/CT)
Oilers (AO) (without carrier bomber)
13
Aviation Cruisers (CAV)
Aviation Battleships (BBV)
Seaplane Tenders (AV)
Light Carriers (CVL)
Landing Ships (LHA)
Oilers (AO) (with carrier bomber)
8
  • [math]\displaystyle{ \text{Mod}_\text{synergy} }[/math] the synergy multiplier bonus from using certain combinations of ASW equips (see below).
Notes
  • The bonuses do not stack, meaning only the highest possible bonus applies.
    • The exception is the depth charge penetration detailed above.
  • Multiple equipments of the same type still only apply the bonus once.
  • There is an accuracy bonus as well but it is small. Stacking sonars will give a bigger accuracy bonus.


Surface Night Battle

Night battle damage stems directly from the sum of Firepower   and Torpedo   of the ship.

Night Attack Formula
[math]\displaystyle{ \text{Night Battle Power} = \text{FP} + \text{TP} + \bigstar + \text{Mod}_\text{contact} }[/math]
With
  • [math]\displaystyle{ \text{Mod}_\text{contact} }[/math] is the Night Battle Contact if   Night Recon is triggered. The value depend of the Accuracy  :
    • 5 for 1  ,
    • 7 for 2  ,
    • 9 for 3  .
Notes

This applies to most ships during Night Battle.

Carrier Night Air Attacks

The carrier night air attack damage calculation is complex but for short only take the stat of the night plane.

Carrier Night Air Attack Formula
[math]\displaystyle{ \text{Atk}_\text{base CNAA} = \text{FP}_\text{ship} + \sum_{\text{All } Night Planes} \text{FP}_\text{night plane} + \text{TP}_\text{night plane} + \uparrow\text{TP}_\text{fit bonus} + \text{DB}_\text{night plane} + \uparrow\text{DP}_\text{fit bonus} + \text{Mod}_\text{contact} + \text{Mod}_\text{Night Plane} }[/math]
With
  • [math]\displaystyle{ \text{Mod}_\text{Night Plane} }[/math] being:
[math]\displaystyle{ \text{Mod}_\text{Night Plane} = \mathrm{A} \times \text{Count}_\text{Plane} + \mathrm{B} \times \left( \text{FP}_\text{night plane} + \text{TP}_\text{night plane} + \text{DB}_\text{night plane} + \text{ASW}_\text{night plane} \right) \times \sqrt{\text{Count}_\text{Plane}} + \sqrt{\bigstar} }[/math]
Notes
  • Unlike daytime carrier attacks, it is possible to attack even if no bombers are equipped.
    • Night fighters are still needed to trigger the attack.
  • Like daytime carrier attacks, carriers are unable to attack if moderately damaged (中破) or worse.
    • Armored carriers are only disabled at heavily damaged (大破).
    • Carriers that can use the night battle shelling formula will use that instead if moderately damaged (中破).
  • The formula only takes into account the base stats of the carrier and night attack capable planes equipped.
    • The Improvement stats are not taken into account.
      • This means any other stats and upgrade bonuses from equipment like guns and non-night-capable planes are ignored.
    • This also means that any Visible Bonus from other planes are also ignored.

This applies to carrier night air attack

Anti-Installation Attacks

Installations differ from regular enemy warships, as they are immune to certain attack elements like the torpedo stat, but are extremely weak against specialized gears.

Support Expedition Attack Power Formula

Support Expedition attack formulas are close but not the same as combat formulas. They also are only affected by the following modifiers:

Shelling Support

Basic attack power is calculated in a similar way as normal for surface ships and carriers except that firepower is reduced by 1.

Surface Attack Formula
[math]\displaystyle{ \text{Atk}_\text{support shelling} = \text{FP} + 4 }[/math]
Notes
  • For support only visible   Firepower is used.
Carrier Shelling Attack Formula
[math]\displaystyle{ \text{Atk}_\text{base carrier shelling} = \bigl\lfloor \left( \text{FP} + \text{TP} + \left[ \text{DB} \times 1.3 \right] - 1 \right) \times 1.5 \bigr\rfloor + 55 }[/math]
Notes
  • Dive and Torpedo groups contribute, respectively, 1.95 and 1.5 times their dive bomb and torpedo stats toward shelling power
  • [math]\displaystyle{ TP }[/math] is the sum of all   torpedo stat any equipment including Fit Bonus.
  • [math]\displaystyle{ DB }[/math] is the sum of all   bombing stat any equipment including Fit Bonus.
    • The inclusion of plane's torpedo Fit Bonus is still inverified.
  • If a carrier is not equipped with any torpedo or dive bombers, she will not participate in shelling support.
    • This also applies if they have lost all bombers during the aerial combat phase.
    • But even if an air group has had all its planes shot down, it will still contribute towards carrier shelling power (if the CV is still capable of attacking).
  • Remember that   improvement bonus does not work in support.
  • Slot sizes and the number of remaining aircraft do not affect carrier attack power during shelling support.
  • Carriers have the easiest time hitting the damage cap. This makes them very powerful assets for support.
  • Planes are not shot down when a carrier participates in shelling.
  • Unlike in normal shelling Hayasui Kai /Yamashio Maru Kai  use the surface shelling formula.

Airstrike Support

Airstrike Support Attack Formula
[math]\displaystyle{ \text{Airstrike Support} = \biggl\lfloor \biggl\{ \text{Type} \times \bigl( \left( \text{DB or TP} \right) \times \sqrt{\text{Count}_\text{Plane} } + 3 \bigr) \biggr\} \times \text{Mod}_\text{crit} \biggr\rfloor \times 1.35 }[/math]
Notes
  • The damage cap of 170 is applied to the result between [math]\displaystyle{ \{ \ \} }[/math].
  • [math]\displaystyle{ \text{Type} }[/math] is the bomber's type modifier, similar to airstrikes.
    • [math]\displaystyle{ 1.0 }[/math] for dive bombers and seaplane bombers.
    • Either [math]\displaystyle{ 0.8 }[/math] or [math]\displaystyle{ 1.5 }[/math] for torpedo bombers.
  • The critical modifier and the 1.35x airstrike support modifier are both post-cap.
  • Is not affected by formation like normal airstrike.
  • The proficiency has no effect on this support.

Anti-Submarine Support

Anti-Submarine Support Attack Formula
[math]\displaystyle{ \text{ASW Support} = \biggl\lfloor \biggl\{ \bigl(\text{ASW} \times \sqrt{\text{Count}_\text{Plane} } + 3 \bigr) \times \left(0.9 + \text{Rand} \right) \biggr\} \times \text{Mod}_\text{crit} \biggr\rfloor \times 1.35 }[/math]
With
  • [math]\displaystyle{ \text{Rand} }[/math] a random number from 0 to 0.75 inclusive.
  • The critical modifier and the 1.35x airstrike support modifier are both post-cap.
  • The damage cap of 170 is applied to the result between [math]\displaystyle{ \{ \ \} }[/math].
Notes
  • Because slot size matters, carriers make much better ASW support ships than light carriers.
  • It has a chance of triggering at every node so consider the enemy compositions of all nodes when running ASW support to help with submarine nodes.
    • A full ASW support setup that runs into enemy airpower will get destroyed.
  • Because even the autogyros and liaison aircraft participate in aerial combat, they can be shot down.
  • It can be useful for chipping down submarines to reduce the number of opening and closing torpedoes faced by the fleet.

Long Range Torpedo Support

Long-Range Torpedo Attack Formula
[math]\displaystyle{ \text{Atk}_\text{base torpedo support} = \text{TP} + 8 }[/math]
With
  • For this formula it's unknown if [math]\displaystyle{ \text{TP} }[/math] include fit bonus or not.
Notes
  • Do not bother using this type of support, since it is by design inferior to the other ones.

LBAS Attack Power Formulas

Anti-Ship
Pre-cap
[math]\displaystyle{ \text{Atk}_\text{pre-cap} = \biggl\lfloor \text{Mod}_\text{type} \times \Big( \big( \text{Mod}_\text{Sp1} \times \text{TP/DB} + \bigstar + \text{Mod}_\text{Sp2} \big) \times \sqrt{1.8 \times \text{Plane}_\text{Count}} + 25 \Big) \times \text{Mod}_\text{Sp3} \times \text{Mod}_\text{LBR} \biggr\rfloor }[/math]
With
  • [math]\displaystyle{ \bigstar }[/math] the Improvement bonuses of the equipment.


Pre-cap modifiers
  • [math]\displaystyle{ \text{Plane}_\text{Count} }[/math] the curent planes count in the slot.
    • It will be 18 (only 9 for LB Heavy Bombers) for fully resupplied bases on their 1st attack.
  • [math]\displaystyle{ \text{Mod}_\text{Sp1}, \text{Mod}_\text{Sp2}, \text{Mod}_\text{Sp3} }[/math] the special modifiers for #LBAS Special Bombers on certain targets,
    • For other planes or against other targets, is 1 for Sp1 & Sp3, and 0 for Sp2.
Post-cap
[math]\displaystyle{ \text{Atk}_\text{post-cap} = \biggl\lfloor \text{Atk}_\text{cap} \biggr\rfloor \times \text{Mod}_\text{Contact} \times \text{Mod}_\text{LBB} \times \text{Mod}_\text{CF} \times \text{Mod}_\text{historical} \times \text{Mod}_\text{boss} \times \text{Mod}_\text{balloon} \times_\downarrow \text{Mod}_\text{crit} }[/math]
Post-cap modifiers
  • [math]\displaystyle{ \text{Mod}_\text{Contact} }[/math] the contact bonus. Please see Contact for more details on the bonus.
  • [math]\displaystyle{ \text{Mod}_\text{LBB} }[/math] being 1.8 for LB Attackers, and 1.0 otherwise.
  • [math]\displaystyle{ \text{Mod}_\text{CF} }[/math] the bonus when attacking combined fleets. It is 1.1 against combined fleets and 1.0 otherwise.
  • [math]\displaystyle{ \text{Mod}_\text{historical} }[/math] being the event historical bonuses.
  • [math]\displaystyle{ \text{Mod}_\text{boss} }[/math] a bonus when attacking certain Princess and Demon-type enemies. The multiplier is chosen randomly between two values. The chance is roughly 50%.
[math]\displaystyle{ \text{Mod}_\text{boss} }[/math][1]
Boss (ID) Low mod High mod
PT Imp (1637-1640)  0.4 0.7
BB Hime (1557)  1.7 3
Summer BB Hime (1696-1698) [2] 1.5? 1.8?
CV Hime (1586)  1.7 3
CV Hime B (2105-2108)  1 1
  • [math]\displaystyle{ \text{Mod}_\text{balloon} }[/math] being the effect of the deployed   Barrage Balloons on both side:
Balloon Effects
  1 2 3
Allied LBAS Damage
Allied balloons [2] 1.02 1.04 1.06
Enemy balloons [3] 0.95 0.90 0.85
  • [math]\displaystyle{ \text{Mod}_\text{crit} }[/math] the critical multiplier of 1.5,


[4]

Anti-Installation
Pre-cap
[math]\displaystyle{ \text{Atk}_\text{pre-cap} = \bigg\lfloor \text{Mod}_\text{type} \times \Big( \big( \text{TP/DB} + \bigstar \big) \times \sqrt{1.8 \times \text{Plane}_\text{Count}} + 25 \Big) \times \text{Mod}_\text{Sp3} \times \text{Mod}_\text{LBR} \bigg\rfloor }[/math]
With
Post-cap
[math]\displaystyle{ \text{Atk}_\text{post-cap} = \biggl\lfloor \text{Atk}_\text{cap} \biggr\rfloor \times \text{Mod}_\text{Contact} \times \text{Mod}_\text{LBB} \times \text{Mod}_\text{CF} \times \text{Mod}_\text{historical} \times \text{Mod}_\text{balloon} \times {\color{tomato}\text{Mod}_\text{Inst}} \times_\downarrow \text{Mod}_\text{crit} }[/math]
  • Other variables are the same as for anti-ship.
  • [math]\displaystyle{ {\color{tomato}\text{Mod}_\text{Inst}} }[/math] is the anti-installation bonus, the multiplier is chosen randomly between two values. The chance is roughly 50%. see here for more details:
[math]\displaystyle{ {\color{tomato}\text{Mod}_\text{Inst}} }[/math][5]
Installation (ID) LBAS
Low mod High mod
 
Isolated Island Princess (1671-1672)
2
 
Artillery Imp (1665-1667)
1.6 2.5
 
"Old" Supply Depot Princesses (1653-1658)
1.7 3.6?
 
"New" Supply Depot Princesses
(B, C, D, ...) (ID>1658)
- -
 
Harbour Summer Princess B (2023)
? ?
ASW
Pre-cap
[math]\displaystyle{ \text{Atk}_\text{pre-cap} = \Big\lfloor \left( \big( \text{ASW} + \bigstar \big) \times \sqrt{1.8 \times \text{Plane Count}} + 25 \right) \times \text{Mod}_\text{ASW} \times \text{Mod}_\text{LBR} \Big\rfloor }[/math]
With
  • [math]\displaystyle{ \text{ASW} }[/math] the ASW   stat of the plane.
  • [math]\displaystyle{ \text{Mod}_\text{ASW} }[/math] a random number based on the base ASW   of the plane. It is between:
    • 0.35 and 0.8 for 7-9 ASW planes.
    • 0.7 and 1.0 for 10+ ASW planes.
Post-cap
[math]\displaystyle{ \text{Atk}_\text{post-cap} = \bigg\lfloor\text{Atk}_\text{cap} \times \text{Mod}_\text{crit} \times \text{Mod}_\text{proficiency} \bigg\rfloor \times \text{Mod}_\text{Contact} \times \text{Mod}_\text{LBB} }[/math]
  • Other variables are the same as for anti-ship.
Note
  • Only "ASW Planes" (7+ ASW) are able to perform ASW attacks.
    • If no aircraft in the base can perform ASW attacks, the base will not show at submarine-only nodes.
Notes
  • Unlike carrier airstrikes, the 1.2x critical proficiency bonus applies to each slot independently.
  • Jet Assault use the airstrike formula even on land base.


Attack Power Corrections

After calculating the basic attack power of the attack being made, it is then adjusted based on various factors. Attack power modifiers can be split into pre- and post-cap modifiers. Post-cap modifiers are more powerful to have because they aren't reduced by the cap.

Pre-cap Modifiers

Engagement

Form Common name Damage Modifier Chance Chance with Saiun 
 
 
Crossing the T (Advantage) Green T 1.2 15% 15%
Parallel Engagement Parallel 1.0 45% 45%
Head-on Engagement Head-on 0.8 30% 40%
Crossing the T (Disadvantage) Red T 0.6 10% 0%

Formation

Formation Attack Power Modifiers
Formation Shelling Torpedo ASW Night Battle
Line Ahead 1.0 1.0 0.6 1.0
Double Line 0.8 0.8 0.8 1.0
Diamond 0.7 0.7 1.2 1.0
Echelon 0.75 0.6 1.1 1.0
Line Abreast 0.6 0.6 1.3 1.0
Vanguard 0.5 1.0 1.0 0.5
1.0 1.0 0.6 1.0

Combined Fleets have special formations that differ from the standard single fleet formations. The following formations can be selected.

Formation Formation Icon Fleet Shelling[1] Torpedo ASW Night Notes
Cruising Formation 1 (ASW Alert)
第一警戒航行序列(対潜警戒)
  Main 0.8 - 1.3 - Moderate shelling and torpedo accuracy.

Similar to Line Abreast.

Escort 0.8 0.7 1.3 ?
Cruising Formation 2 (Forward Alert)
第二警戒航行序列(前方警戒)
  Main 1.0 - 1.1 - Higher shelling and torpedo accuracy than Formation 1.

Similar to Double Line without the accuracy bonus.

Escort 1.0 0.9 1.1 ?
Cruising Formation 3 (Ring Formation)
第三警戒航行序列(輪形陣)
  Main 0.7 - 1.0 - Requires 5 or more ships in the 2nd fleet. Very low shelling and torpedo accuracy.

Similar to Diamond.

Escort 0.7 0.6 1.0 ?
Cruising Formation 4 (Battle Formation)
第四警戒航行序列(戦闘隊形)
  Main 1.1 - 0.7 - Requires 4 or more ships in the 2nd fleet. Highest shelling and torpedo accuracy.

Similar to Line Ahead.

Escort 1.1 1.0 0.7 ?

The following tab resume when engagement and formation are effective:

Modifier LBAS Airstrike Support Shelling Torpedo ASW Night Battle
Shelling Aerial Torpedo Surface Carrier
Engagement ✔️ ✔️ ✔️ ✔️ ✔️ ✔️ ❌*
Formation ✔️ ✔️ ✔️ ✔️ ✔️ ✔️ ✔️
Note
  • If one of the fleet si a combined one then the formation modifier become 1 for the support.

Damage State

Damage State Shelling Torpedo ASW
Not Damaged 1.0 1.0 1.0
Lightly Damaged (小破)
Moderately Damaged (中破) 0.7 0.8 0.7
Heavily Damaged (大破) 0.4 0 0.4
Notes
  • Damage state does not affect aerial combat.
    • It will affect carrier attacks in the shelling phase.


Night Battle Cut-In

Night Cut-Ins will apply extra modifiers if triggered.

[math]\displaystyle{ \text{Mod}_\text{CI} }[/math]
"New" Cut-ins
Attack Type Prerequisites Notes Damage
Modifier
Destroyer Cut-ins    Surface 1.3
With 12.7cm Mod D K2  1.625
With 12.7cm Mod D K3  1.706
With 2 12.7cm Mod D K2  1.820
With both 12.7cm Mod D K2  & K3  1.911
With 2 12.7cm Mod D K3  2.002
  Surface  1.2
With 12.7cm Mod D K2  1.5
With 12.7cm Mod D K3  1.575
With 2 12.7cm Mod D K2 [1] 1.680
With both 12.7cm Mod D K2  & K3 [1] 1.768
With 2 12.7cm Mod D K3 [1] 1.848?
    Requires TSLO  1.5
    Requires TSLO  1.3
Carrier Cut-ins[2]       =      1.25
   1.2
  
OR
   
1.2
     1.18
Night Zuiun Cut-ins      Surface - 1.36
     1.32
    Surface 1.28
    1.24
[math]\displaystyle{ \text{Mod}_\text{CI} }[/math]
"Old" Cut-ins
Attack Type Prerequisites Damage
Modifier
Gun Cut-in     2
Mixed Gun Cut-in     1.75
Submarine Cut-ins  Sub_LM   1.75
 Sub_LM  Sub_LM 1.6
Torpedo Cut-in    1.5
Mixed Torpedo Cut-in    1.3
Double Attack    1.2
  
  

ASW Synergy

ASW Damage Synergy
 Small Small Sonars
 
Type 93 Passive Sonar
 
Type 4 Passive Sonar
 
Type 3 Active Sonar
 
Type 3 Active Sonar Kai
 
Type124 ASDIC
 
Type144/147 ASDIC
 
HF/DF + Type144/147 ASDIC
 Large Large Sonars
 
Type 0 Passive Sonar
 DCP Depth Charge Projectors (DCP)
 
Type 94 Depth Charge Projector
 
Type 3 Depth Charge Projector
 
Type 3 Depth Charge Projector (Concentrated Deployment)
 
Prototype 15cm 9-tube ASW Rocket Launcher
 
RUR-4A Weapon Alpha Kai
AP
 
Mk.32 ASW Torpedo (Mk.2 Thrower)
AP
 DCR Depth Charge (Racks) (DCR)
 
Type 95 Depth Charge
AP
 
Type 2 Depth Charge
AP
 
Lightweight ASW Torpedo (Initial Test Model)
AP
 
Hedgehog (Initial Model)
AP
 
Type 2 Depth Charge Kai Ni
AP
 Other ASW Mortars
 
Type 2 12cm Mortar Kai
 
Type 2 12cm Mortar Kai (Concentrated Deployment)
ASW Damage Modifiers: [math]\displaystyle{ \text{Mod}_\text{synergy} = {Mod}_\text{1} \times {Mod}_\text{2} }[/math]
[math]\displaystyle{ {Mod}_\text{1} }[/math]   +  
(Any Sonar + Any Depth Charge)
1.15
[math]\displaystyle{ {Mod}_\text{2} }[/math]  DCP +  DCR and NO  Small 1.1
 Small +  DCP +  DCR 1.25
Examples
[math]\displaystyle{ \text{Mod}_\text{synergy} }[/math]  Small +  DCP +  DCR 1.4375[math]\displaystyle{ 1.15 \times 1.25 }[/math]
 Large +  DCP +  DCR 1.265[math]\displaystyle{ 1.15 \times 1.1 }[/math]
Armor Penetration
Indepentant of synergies, some equipment provides additional armor penetration to ASW attacks.

The flat armor penetration value is calculated as follows:

[math]\displaystyle{ \text{Pen} = \sum\limits_{\text{Equipment}} \Big( \sqrt{\text{ASW}_\text{Equipment} - 2} + \text{Mod}_\text{ship} \Big) }[/math]
With
  • [math]\displaystyle{ \text{ASW}_\text{Equipment} }[/math] the base ASW   stat of the applicable equipment,
  • [math]\displaystyle{ \text{Mod}_\text{ship} }[/math] being 1 for DE, 0 otherwise,
Note
  • Armor penetration from equipment stacks,
  • The final armor of the targetted submarine cannot go below 1.


Special Attack Bonus

The Special attacks modifier are post-cap for day battle. But are pre-cap for night battle.


Hidden Fit Bonuses

Unlike the other pre-cap bonuses, this is just a minor additive firepower bonus added for some ships (mostly cruisers) when equipped with certain guns.

Post-cap Modifiers

Aerial Contact

During aerial combat, there is a chance for the ships to trigger Contact. When it is triggered, the is a bonus multiplier applied to airstrike damage depending on the Accuracy   of the plane that triggered contact.

Accuracy   Damage Modifier
0 1.12
1 1.12
2 1.17
3+ 1.2


Airstrike Special Bonus

There's a bonus when attacking certain Princess and Demon-type enemies during airstrike. The multiplier is chosen randomly between two values. The chance is roughly 50%.

[math]\displaystyle{ \text{Mod}_\text{boss} }[/math][3]
Boss (ID) Low mod High mod
PT Imp (1637-1640)  0.5 0.8
BB Hime (1557)  1.4? 2.2?
Summer BB Hime (1696-1698) [4] 1.3? 1.8?
CV Hime (1586)  1.7? 2.2?
CV Hime B (2105-2108)  1.7? 2.2?

Artillery Spotting

Attack Type Prerequisites Post-cap
Damage
Modifier
Notes
Main Zuiun Cut-in
(Zuiun CI)
    1.35 Ise-class Kai Ni 
 
only
Main Suisei Cut-in
(Suisei CI)
    1.3
Main AP Shell Cut-in
(APCI)
     1.5
Secondary AP Shell Cut-in
(Sec APCI)
     1.3
Secondary Radar Cut-in
(Radar CI)
     1.2
Secondary Cut-in
(Sec CI)
    1.1
Double Attack
(DA)
    1.2


Carrier Cut-In Attacks

Attack Type Prerequisites Post-cap
Damage
Modifier
Fighter-Bomber-Attacker
(FBA)
    1.25
Bomber-Bomber-Attacker
(BBA)
    1.2
Bomber-Attacker
(BA)
   1.15

If a CVCI attack is evaded, it will deal Scratch Damage instead.


Armor-Piercing Modifier

During day combat, certain enemy ships take extra damage from   AP Shells 
 
 
.

  • The bonus only applies against FBB, BB, BBV, CV, CVB, CA, and CAV.
    • This includes Installations.
    • This means that this bonus does not apply against all other types, namely CVL, CL(T), CT, DD, DE, SS(V), AV, AS, AR, LHA, or AP.

For clarity purposes:

Type Modifier
   1.08
    1.10
   
    
1.15
Note
  • It is unadvisable to run any of the other setups beyond the most basic Gun+AP, as the other setups will interfere with artillery spotting and give worse bonuses.
  • This modifier doesn't affect support shelling.

Barrage Balloon Modifier

 
Example of a balloon deployed.

  Barrage Balloons can be deployed in certain situations during day battles.

Barrage Balloons can only be deployed on certain combat nodes with Installations
Compatible Nodes
Map Node Notes
3-5 H
4-3 N Boss
4-5 T Boss
6-4 N Boss
Events Refers to the current event page
references [6][7][8][9]
Once deployed
  • For every ship with a balloon equipped will boost the damage of the fleet and the LBAS (post-cap):
Balloon Effects
  1 2 3
Allied Day Shelling Damage
Allied balloons [10] 1.02 1.04 1.06
Allied LBAS Damage
Allied balloons [11] 1.02 1.04 1.06
Enemy balloons [12] 0.95 0.90 0.85
  • The effect stacks up to 3 balloons, and up to 1 balloon per ship,
  • The effect applies to LBAS and day shelling, with the enemy balloons also negatively affecting allied LBAS,
  • The effect does not apply to torpedo phases or night battles,
  • If the ship deploying it is sunk, the balloon is then removed, as well as its effects.


Anti-Installation Equipment Modifiers


Special Attack Bonus

The Special attacks modifier are post-cap for day battle. But are pre-cap for night battle.

Criticals

For more details on how critical chance is calculated, please see Critical.

Normal Criticals
Attack Type Modifier
Normal 1.0
Critical [math]\displaystyle{ 1.5 \times \text{Mod}_\text{proficiency} }[/math]
Plane Proficiency Critical Modifier

Ammunition Modifier

The damage of the fleet is reduced once their ammunition falls below 50%. This modifier cannot go above 1. The formula used to determine this is:

[math]\displaystyle{ \text{Ammo} }[/math] formula
[math]\displaystyle{ \text{Ammo} = \dfrac{\Big\lfloor \dfrac{\text{Current Ammo} }{\text{Max Ammo} } \times 100 \Big\rfloor}{50} }[/math]
With
  • [math]\displaystyle{ \text{Current Ammo} }[/math] the current ammo of the ship.
  • [math]\displaystyle{ \text{Max Ammo} }[/math] the max ammo of the ship (indicated under consuption on the ship info).
Remaining Ammo Ammo Modifier Notes
>50% 1.0
40% 0.8 4th Battle
30% 0.6
20% 0.4 5th Battle
10% 0.2
0% 0 6th Battle
  • The battle number indicated in the notes assumes only normal surface engagements. Engaging in night battles and other special engagements can change that number.
  • Whatever ammunition modifier applies in day battle carries over to night battle.
  • Maelstroms that reduce ammunition also count towards this modifier.
  • Using   Underway Replenishment  is a way to medigate ammo penalties.
  • The ammunition modifier affects aerial battle.
  • Once a ship hits 0% ammo, all attacks become scratch damage.
  • Debuffs are affected by the ammunition modifier.

Miscellaneous Damage Modifiers

Scratch Damage

In the following cases, attacks will deal "scratch damage" instead of normal ones:

  • If a Cut-in or a special attack is evaded;
  • The target's armor cannot be penetrated (attack inferior to eh enemy defense);
  • The ammo count hits 0;
  • When a single fleet attack submarine during night battle;
    • ASW attack works as usual on Night Battle nodes and Night to Day Battle node;
  • When a Friendly Fleet attacks the last remaining ship of an enemy fleet.

Scratch damage is dealt as a percentage of remaining HP calculated using the following formula:

Scratch Damage formula
[math]\displaystyle{ \text{Damage}_\text{scratch} = \text{HP}_\text{current} \times 0.06 + \text{HP}_\text{rand} \times 0.08 }[/math]
With
  • [math]\displaystyle{ \text{HP}_\text{current} }[/math] the current HP   of the target.
  • [math]\displaystyle{ \text{HP}_\text{rand} }[/math] a random HP number between 0 and [math]\displaystyle{ \text{HP}_\text{current} - 1 }[/math]

Therefore the maximum possible scratch damage [math]\displaystyle{ \text{HP}_\text{current} \times 0.14 - 0.08 }[/math] and the minimum damage is [math]\displaystyle{ \text{HP}_\text{current} \times 0.06 }[/math].

  • If the target's HP is low, it is possible for the result of the formula to return a result of 0. Remember that all formulas are rounded down.
    • This means the target's HP cannot be reduced to 0 by scratch damage.
Friendly Fleet

A Friendly Fleet cannot kill the last ship of the opposing fleet, dealing special scratch damage instead.

[math]\displaystyle{ \text{Damage}_\text{scratch} = \text{HP}_\text{current} \times 0.5 }[/math]
  • Scratch damage is generally between 6-14% of current HP.

The target's HP cannot be reduced to 0 (and therefore sunk) by scratch damage.

PT Imps

Anti-PT boat
Unlike most standard Abyssals, "PT boats" (PT Imp Pack  & Schnellboot Imp Pack ) are "very small and fast".
  • All ship types suffer a severe   accuracy and   firepower penalty against PT boats.
  • Attacking them with larger guns is not very effective, smaller guns being recommended instead.
  • Support Expeditions are not affect by any of the following[1].
Attack formula against PT boats
The Attack formula against PT boats:[2][3]
Jet Assault & Airstrike
  • [math]\displaystyle{ \text{Damage}_\text{PT}= \text{Atk}_\text{post-cap} \times \text{Rand} [0.5 ; 0.8] }[/math]


LBAS[4]
  • [math]\displaystyle{ \text{Damage}_\text{PT}= \text{Atk}_\text{post-cap} \times \text{Rand} [0.4 ; 0.7] }[/math]


Shelling
  • [math]\displaystyle{ \text{Damage}_\text{PT}= ( 0.3 \times \text{Atk}_\text{post-cap} + \sqrt{\text{Atk}_\text{post-cap}} + 10 ) \times \prod^{All Equipment}{\text{Mod}_\text{EquipmentAtk}} }[/math]


Opening & Closing Torpedo Salvos
  • [math]\displaystyle{ \text{Damage}_\text{PT}= 0.3 \times \text{Atk}_\text{post-cap} + \sqrt{\text{Atk}_\text{post-cap}} + 10 }[/math]


Night Battle
  • Night Battle data are unclear yet.


With
  • [math]\displaystyle{ \text{Atk}_\text{post-cap} }[/math] the post cap attack power defined here,
  • [math]\displaystyle{ \text{Mod}_\text{EquipmentAtk} }[/math] the bonuses given by equipment, described below.
Accuracy formula against PT boats
The Accuracy formula against PT boats:[5][6][7][8]
[math]\displaystyle{ \text{Hit Rate}_\text{vs.PT} \text{%} = \Big\lfloor ( 0.3 \times \text{Accuracy}_\text{Atk} + \sqrt{\text{Accuracy}_\text{Atk}} + 15 ) \times 1.2 \times \text{Mod}_\text{Ship} \times \Big( \prod^{All Equipment}{\text{Mod}_\text{EquipmentAcc}} \Big) \times \text{Mod}_\text{Night} \Big\rfloor - \text{EVA}_\text{PT} + 1 }[/math]
With
  • [math]\displaystyle{ \text{Acc}_\text{Atk} }[/math] the standard accuracy described here
    • PT boats are "DDs" in the game, so the [math]\displaystyle{ \text{Mod}_\text{formation} }[/math] for vanguard is 1.1 during shelling, and 1.2 during the torpedo phase.
    • Historical accuracy bonuses during Events are included in the Standard Accuracy Term, i.e. it is affected by the [math]\displaystyle{ \text{Mod}_\text{PT} }[/math] modifier.
  • [math]\displaystyle{ \text{EVA}_\text{PT} }[/math] the PT estimated evasion   described bellow,
PT boats stats
Type Luck   Eva   [math]\displaystyle{ \text{EVA}_\text{PT} }[/math]
Line Ahead  Echelon  Line Abreast 
PT Imp Pack  ? ? 81? 87? ?
PT Imp Pack II  60 220 80 87 85
PT Imp Pack III  60 250 82 89 88
PT Imp Pack IV  ? ? ? 84? ?
Schnellboot Imp Pack  ? ? ? ? ?
Schnellboot Imp Pack II  ? ? ? ? ?
Schnellboot Imp Pack Elite  ? ? ? ? ?


The main Accuracy modifiers are
  • [math]\displaystyle{ \text{Mod}_\text{Amagiri} }[/math] being include in [math]\displaystyle{ \text{Acc}_\text{Atk} }[/math]:
  • [math]\displaystyle{ \text{Mod}_\text{Ship} }[/math] the bonus given by ship types, described below,
  • [math]\displaystyle{ \text{Mod}_\text{EquipmentAcc} }[/math] the bonuses given by equipment, described below,
  • [math]\displaystyle{ \text{Mod}_\text{Night} }[/math] being 0.7 during night battle, 1 during day battle.


Amagiri Kai Ni/D 
 
has the ability to prioritize focusing on attacking PT imps with significantly increased accuracy if any are present.

  • DD placed in the composition slots above and below her will gain a noticeable accuracy boost and will prioritize attacking PT boats if any are present.
  • The PT boat targeting rate is 100% for all affected ships [9].

During Events, some special bonuses may be added, with "historical" ships and equipment gaining some accuracy bonuses[10].

Ship Type [math]\displaystyle{ \text{Mod}_\text{Ship} }[/math]
DD & DE 1.0
CL, CLT, & CT 0.82
All other types 0.7
Equipment [math]\displaystyle{ \text{Mod}_\text{EquipmentAcc} }[/math] [math]\displaystyle{ \text{Mod}_\text{EquipmentAtk} }[/math]
1st equipped 2nd equipped 1st equipped 2nd equipped
  Small Small Caliber Main Guns[11] 1.3 1.15 1.5 2.11.5×1.4
  Sec Secondary Guns[12] 1.55 1 1.3
  Anti-Aircraft Guns 1.45 1.35 1.2 1.441.2×1.2
  Skilled Lookouts 
 
1.75 1 1.1
 Armed Soukoutei (Armored Boat Class)  1.45 1.3 1.2 1.1
Armed Daihatsu  1.45 1.3 1.2 1.1
  Ka-Tsu Tanks 
 
[13][14]
1 1.3 1 1.1
 Bomber  Seaplane Bombers & Seaplane Fighters 1.5 1 1.2
    Dive Bombers & Jets 
 
1.375 1.2 1.4 1.821.4×1.3
All other equipment 1 1
Notes
  • It is recommended to use anti-PT setups on DDs only, such setups compromising overall combat effectiveness.
  • Having a Reinforcement Expansion is important because it can save a ship slot by containing a machine gun or skilled lookouts.
  • Combining equipment is recommended to see significant boosts to accuracy.
  • The   Ka-Tsu Tanks 
     
    bonus does not stack with the   Armed Boats 
     
    ones.
  • Using other setups improving accuracy is also advisable:
References:
[edit]

Historical Bonus

On almost every Event map, as well as some regular maps (7-4 & 7-5 so far), certain ships, types of ships, equipment, or types of equipment will bring bonuses.

  • Those bonuses are most of the time raw damage multipliers, and sometimes, accuracy bonuses.
  • Bonuses are independent to each ship, so only the ships with any historical bonus or ships equipped with historical equipment will be affected.
  • Bonuses may be applicable to some parts of a map only, such as specific phases of nodes.

This mechanic is here to encourage the use of "historically significant fleets and setups".

  • By nature, historical bonuses are arbitrary, so refer to each individual map to see what bonuses are applicable.

Summer Mode Bonuses

There are consistent bonuses against the following abyssal bosses' summer forms. These bonuses may differ on some event's maps.

Damage Bonuses
       
Ships
[Toggle Names]
 
Ark Royal Kai
 
Bismarck Drei
 
Nelson Kai

 
Prinz Eugen Kai
 
Gotland Andra
1.1x -
 
Richelieu Deux
 
Jean Bart Kai
 
Commandant Teste Kai

 
Mogador Kai
 
Gloire Kai
- 1.15x
Equipment   AP Shells 
 
 
1.2x 1.1x 1.1x 1.2x
 Bomber SPB
  SPF
1.1x 1.15x 1.1x 1.1x
 Bomber Laté 298B  - 1.32x1.1 x 1.2
  Swordfish 
 
 
1 = 1.15x
2 = 1.32x
1 = 1.15x
2 = 1.21x
1 = 1.1x
2 = 1.21x
-
  Dive Bombers - 1 = 1.1x
2 = 1.32x
1 = 1.1x
2 = 1.265x

The Laté 298B  bonus includes the SPB bonus.

Foreign Plane Bonuses

"Foreign Plane Bonuses" is an event-only mechanic where most foreign planes (not from the IJN/IJA) get various damage bonuses.

Debuffs

Debuffs are a special case that only applies during events.

Certain event maps have debuff mechanics that require completing certain gimmicks once Last Dance is reached, in order to trigger the boss or boss' fleet debuff.

  • See here for more details on past event debuffs.

Debuffs can be either:

  • A reduction to the enemy's armor  ,
  • A post-cap damage modifier for the attacking fleet (probably cases of miss interpretation of armor reductions).

Overkill Protection

When a ship in the fleet takes more damage than her current HP, she will take a percentage of her current HP in damage instead.

  • The ship must be the flagship OR
  • The ship must not be heavily damaged (大破) nor red morale   at the start of the battle.
    • If the ship has red morale, she will just have her HP reduced to 1.


Overkill formula
[math]\displaystyle{ \text{Damage}_\text{Overkill} = \text{HP}_\text{current} \times 0.5 + \text{HP}_\text{rand} \times 0.3 }[/math]
With
  • [math]\displaystyle{ \text{HP}_\text{current} }[/math] is the current HP   of the ship.
  • [math]\displaystyle{ \text{HP}_\text{rand} }[/math] is a random HP number between 0 and [math]\displaystyle{ \text{HP}_\text{current} - 1 }[/math]
Notes
  • Therefore, the maximum damage from overkill protection is [math]\displaystyle{ \text{HP}_\text{current} \times 0.8 - 0.3 }[/math] and the minimum damage is [math]\displaystyle{ \text{HP}_\text{current} \times 0.5 }[/math].

Overkill protection will take off between 50-80% of the ship's current HP  .

Important Information
  • In general:
    • Overkill protection is most applicable to DDs.
      • The most pronounced effects of overkill protection occur at low HP
      • It is also the primary means of surviving a hit they fail to evade
      • For example, a 32HP DD has a 15.5% chance of being heavily damaged (大破) by a BB Hime, while a 31 HP DD has just a 6.5% chance
      • This has great implications when marrying ships, 36 HP has one of the highest chances of a taiha
    • Odd-numbered HP is better when overkill protection is triggered. This is because the damage calculations round down, reducing the likelihood of being knocked down to heavy damage.
    • This mechanism is most applicable to ships at full HP. Once a ship starts taking damage, the utility of overkill protection diminishes
  • Generally ships with HP that are divisible by 4 have worse survivability.

See Also