Combat/Night Battle

Night Battle Breakdown

The screen after Day Battle. Clicking "夜戦突入" on the right will begin Night Battle

When the fleet pursues the enemy into Night Battle (夜戦, yasen), or enters special Nodes such as Night Nodes or Night to Day Nodes, the fleet will fight at night.

The Night Battle has the following structure:

• Night Contact and Spotting
• Night Shelling Phase

Other phases that may happen before Night Shelling Phase:

• Support Expedition (if the battle starts at night)
• Allied Friendly Fleet Phase

In case neither fleets meet the requirements, the sub-phase will be skipped.

Night Contact and Spotting

Star Shell, Searchlight, and Night Recon activated. The Night Recon is displayed on top of the Enemy "Radar".

When the fleet is equipped with certain equipment, additional effects are triggered for the duration of the Night Battle. The relevant equipment and their effect are listed below.

• More information on the actual effects on cut-in rate of each piece of equipment can be found in the Night Shelling Special Attacks section.
• See Accuracy, Evasion and Criticals for details on other effects.

Equipment	Effect	Requirements
Star Shell	Increases the of the fleet. Increases the cut-in rate of the fleet. Greatly decreases the cut-in rate of the enemy fleet.	Ship must have at least 5 HP Trigger rate is 70% per ship equipped with a Star Shell. If multiple Star Shells are in the fleet, each will have a chance to trigger in fleet order.
Prototype Night Zuiun (Attack Equipment)		Trigger the Night Zuiun CI. Effect apply only after the Night Zuiun CI triggered.
Searchlights	Greatly increases the of the fleet. Greatly increases the cut-in rate of the fleet. Decreases the cut-in rate of the enemy fleet. The equipping ship has its evasion sharply reduced, and is targeted more often. Improvements enhance those effects.	Ship must have at least 2 HP Trigger rate is 100%
Skilled Lookouts	Increases the cut-in rate of the ship equipping it.	None
Night Recons	Increases the of the fleet. Increases the stat of the entire fleet by 5 for the Type 98 Night Recon, 7 for the Type 0 Night Recon & Loire 130M. Increases the critical hit rate of the fleet.	The recon cannot trigger on a slot of size 0. The success rate is dependent on the level of the ship it is equipped on. Trigger is determined by: [math]\displaystyle{ \text{Triggers %} = 4 \times \bigg\lfloor \sqrt{\text{LoS}} \times \sqrt{\text{LV}} \bigg\rfloor }[/math] With: [math]\displaystyle{ \text{LoS} }[/math] The base LoS of the recon (excluding Improvements and fit bonuses), [math]\displaystyle{ \text{LV} }[/math] The Level of the ship carrying the Night recon. Like Day Contact, if multiple night recons are in the fleet, each will have a chance to trigger, in base accuracy order. If the Night Battle was preceded by a day battle: The Air State must be AD, AS or AS+.

Night Shelling Phase

Following the battle preliminary stages, Night Shelling proper will begin. Similar to Day Battle, attacks performed by ships are shelling attacks.

Some rules are applied to shelling attacks:

• Attack power is defined by + stats instead of only .
  • It is often represented with the "Night Battle Power" (Yasen) icon.
  • If the enemy is unaffected by torpedoes, such as installations, only is used instead.
• Heavily damaged (大破) and sunk ships are unable to participate in battle.
• CV(B/L) are unable to participate in battle, unless specific requirements are met. See Carrier Night Attacks.
• Shelling attacks that target submarines will always deal 0 damage, and default to scratch damage, making it impossible to sink submarines during Night Battle.
  • This rule is void if the player fleet is a Combined Fleet.
  • Friendly Fleets also ignores this rule and may damage submarines.
• Ships with 0 stat are unable to participate in night battle.
  • Currently, this is only observable against the Wa-Class Transport Ship.
• Some ship types gain bonus Evasion :
  • CA(V) gain +5 evasion.
  • DD gain +10 evasion if equipped with a Skilled Lookout
    and a Surface Radar.
• CA(V) equipped with IJN 20.3 cm guns
  
  gain hidden accuracy fit bonus.

Example of engagement order during Night Battle

The firing order is defined when the Night Shelling Phase starts, and in contrast to Day Battle, will not skip over sunk and retreated ships, or ships that have no means of attacking under any circumstances, such as a carrier with no bombers equipped or a Wa-Class Transport Ship, for example. In such cases, the ship will perform an actionless turn instead.

In addition to that, Night Battle is not affected by the Day Battle's Engagement.

Carrier Night Attacks

Normally carriers cannot attack at night unless certain conditions are fulfilled. There are three different kinds of carrier night attacks: Standard Shelling, Swordfish Night Attacks, and Carrier Night Air Attacks.

This is not to be confused with Carrier Cut-In Attacks which are for daytime shelling.

Trigger Requirements

1. Standard Shelling

• Graf Zeppelin
  (both remodels), Taiyou-class Kai Ni
  
  , Saratoga (base only), and Kaga Kai Ni Go are able to attack at night with guns regardless of equipment.
• This attack can be triggered even when moderately damaged (中破).
• The attack power is calculated using the surface night battle damage formula.
  • Because of this, these attacks are weak.
• There is no critical multiplier bonus from plane proficiency.
• If the enemy fleet contains a submarine, the light carriers will be forced to target them.
• May be set up to activate Double Attacks and Cut-Ins.

2. Swordfish Night Attack

• This is just limited to Ark Royal
  (both remodels) when equipped with a Swordfish
  
  .
• This attack cannot be triggered when moderately damaged (中破).
• The attack power is calculated using the surface night battle damage formula but only taking into account Ark Royal's base firepower and the Swordfish's stats.
  • All other equipment stat/bonuses are ignored.
  • Swordfish fit bonuses are also ignored.
  • However the Swordfish improvement is taken into account
• There is a critical multiplier bonus from plane proficiency.
• May be set up to activate Double Attacks and Cut-Ins.

On a side note, unlike the browser version, on the arcade version the attack is very powerful.

3. Carrier Night Air Attack

• When equipped with a NOAP
  along with at least one night plane, all carriers are able to perform carrier night air attacks.Night Carriers (CVN) are CV/CVL capable of Carrier Night Air Attacks without needing a NOAP
  . They are Saratoga Mk.II, Akagi Kai Ni E, Kaga Kai Ni E, and Ryuuhou Kai Ni E.
• This attack cannot be triggered when moderately damaged (中破).
  • Armoured carriers can still trigger the attack at moderate damage.
• The attack power is calculated using the carrier night air attack formula.
  • Only the base stats of the carriers and the stats of the night planes are taken into account.
  • Slot size plays a role in determining damage.
  • Planes in slots that have been reduced to 0 are ignored.
• It can trigger regardless of the result of the fighter combat phase in day.
• It can trigger even if no bombers are left.
• There is a critical multiplier bonus from plane proficiency.
• Light carriers will ignore submarines to target surface ships with this attack.
• May activate Night Carrier Cut-Ins.

Night Special Attacks

Using special equipment setups, ships may perform one of multiple special attacks at night. These attacks are often referred to as Cut-ins due to the way the equipment is displayed on the screen before the attacks are performed. Particular Cut-ins are often referred to by their acronym, such as TCI for Torpedo Cut-in, GCI for Gun Cut-in, etc.

Compared to its Day Battle counterpart Artillery Spotting, Cut-ins require no special conditions such as Air State, relying solely on the equipment restrictions and the stats of the ship performing it. Do note that the specific equipment being shown during the Cut-ins have no influence on the damage output.

Cut-ins may be activated during a ship's turn and will override its normal single attack.

In addition, all "Special Attacks" (Touches) can trigger at night, with the "Kongou-Class Night Assault" being only available during night battle.

Setups and Attack Types

Different setups have different conditions, trigger rates, damage, and number of hits. Cut-ins are solely determined by the attack's prerequisites.

For a given Cut-in, any other equipment can be added to the remaining slots. Be wary that adding certain equipment may change the Cut-ins rolled for. If the setup fulfills multiple prerequisites, the Cut-in closer to the bottom of the list will be used. Additionally, each ship will roll for "New Type" Cut-ins first, if possible.

• is used to indicate a Main Gun.
• is used to indicate a Secondary Gun.
• is used to indicate a Torpedo (including Submarine Torpedoes).
• is used to indicate Night Seaplane Bomber.
• Custom icons are used for Carrier Cut-ins for clarity's sake.
  • is used to indicate either a Swordfish
    
    or Iwai F/B.
  • is used to indicate a Night Fighter.
  • is used to indicate a Night Torpedo Bomber.
  • is used to indicate Suisei Model 12 (w/ Type 31 Photoelectric Fuze Bombs) (a.k.a. "Photobomber").

Special attacks that hit twice will roll independently to determine hit, critical chance, and armor penetration. Although their animations appear as single hits, Torpedo Cut-In, and Mixed Torpedo Cut-In are actually composed of 2 separate hits, with their damage added together in-game.

"New Type" Cut-ins

Uranami performing a DD-exclusive Torpedo/RADAR/Lookout Cut-in, or TRL for short.

The "New Type" Cut-ins are the Cut-ins introduced with the implementation of Saratoga Mk.II onwards. From top to bottom, each eligible Cut-in will be rolled if the previous roll has failed. If all rolls fail, then an additional single roll for a "Original Type" Cut-in is performed.

Do note that Night Carrier Cut-ins require a CV(L/B) with Night Operation capabilities by either equipping a NOAP
or being a CVN.

• Carriers that can perform Surface Shelling attacks at night will not perform Carrier Cut-ins without said Night Operation capabilities.

Night Zuiun CI

(Exact effects are still under investigation)

• Must be equipped on a CL, CAV, BBV, or AV to trigger.
• The ship must not be more than lightly damaged (小破).
• Performs 2 attacks against random enemies.
  • The same enemy can be targeted twice.
• Drops a Star Shell during the attack.
• Equipping a Surface Surface Radar or additional NSPB can further increase the effectiveness (trigger rate?/damage?).

If not applicable, ships will skip rolling for "New Type" Cut-ins altogether and only roll for Original Types instead.

Attack Type	Prerequisites	Notes	Pre-cap Damage Modifier	Hits	Chance for 2nd Hit LV 80+ DD only
Destroyer Cut-ins			1.3	1 or 2	65%
		With 12.7cm Mod D K2	1.625
		With 12.7cm Mod D K3	1.706
		With 2 12.7cm Mod D K2 (Tashkent Kai only)	2.031
		Synergy with evasion bonus	1.2		50%
		With 12.7cm Mod D K2	1.5
		With 12.7cm Mod D K3	1.575
		Requires TSLO	1.5		87.5%
		Requires TSLO	1.3		~55%?
Carrier Cut-ins		=	1.25	1	N/A
			1.2
	OR		1.2
			1.18
Night Zuiun Cut-ins			1.25	2*Will fire at 2 random enemies	N/A
		With a Surface	?
		With a second	?

Derivated set-ups

When using an SLO or TSLO in the Reinforcement Expansion, it is possible to "mix" the Destroyer Cut-ins, making 2 cut-ins available to trigger at once, and so increasing the odds of having at least one that activates during Night Battle.

Those set-ups are:

• "GTRL":
• "DTRL":

GTRL is sometimes referred to as "GUiTaRSolo" for "Gun, Torp, Radar, and Skilled Lookouts (SLO)".

Original Cut-ins

In contrast with the "New Type" Cut-ins, Original Cut-ins are only rolled once, even if multiple setup prerequisites are met. The setup used will be the top-most that meets the prerequisites. If this roll fails, the ship will perform a Single Attack.

Attack Type	Prerequisites	Notes	Pre-cap Damage Modifier	Accuracy Modifier	Hits
Gun Cut-in		+ Any on the remaining slots	2	2	1
Mixed Gun Cut-in		No additional	1.75	1.5
Submarine Cut-ins	Sub_LM	With Late-Model Sub Torps ONLY	1.75	?	2
	Sub_LM Sub_LM		1.6
Torpedo Cut-in		+ Any on the remaining slots	1.5	1.65
Mixed Torpedo Cut-in		Additional allowed	1.3	1.5
Double Attack		No additional	1.2	1.1
		Additional allowed
		Additional allowed

Single Attack

If all rolls fail or the ship meets no Cut-in requirements, then it'll perform a Single Attack: a default 1 hit, no damage modifier attack.

Trigger Rates

The chance of successfully rolling a Cut-in and performing the attack is given by:

[math]\displaystyle{ \text{CI %} = \left[ \dfrac{\text{Base}_\text{ship}}{\text{Base}_\text{attack}} \right] \times 100 }[/math]

Where:

[math]\displaystyle{ \text{Base}_\text{ship} = \lfloor 15 + \text{Luck} + 0.75 \times \sqrt{\text{Level}} + \text{Modifiers}\rfloor }[/math] , if the Ship's Luck stat is less than 50.

[math]\displaystyle{ \text{Base}_\text{ship} = \lfloor 65 + \sqrt{ \left( \text{Luck} - 50 \right) } + 0.8 \times \sqrt{\text{Level}} + \text{Modifiers}\rfloor }[/math] , if the Ship's Luck stat is 50 or greater.

Modifiers is the sum of various equipment modifiers. Do note that modifiers change based on the Cut-in that is being used:

Modifier		Value	%
			Gun Cut-in	Mixed Gun Cut-in	Torpedo Cut-in	Mixed Torpedo Cut-in
Placement	Flagship	15	10.7%	11.5%	12.3%	13%
	Other	0	0%
Health	Moderate damage (中破 Chuuha)	18	12.9%	13.8%	14.8%	15.7%
	All other health states	0	0%
Searchlights	Allied	7	5%	5.4%	5.7%	6.1%
	Enemy	-5	-3.6%	-3.8%	-4.1%	-4.3%
Star Shell	Allied	4	2.9%	3.1%	3.3%	3.5%
	Enemy	-10	-7.1%	-7.7%	-8.2%	-8.7%
Skilled Lookouts	Allied	5	3.6%	3.8%	4.1%	4.3%
	Enemy	0	0%
Torpedo Squadron Skilled Lookouts	Allied DD/CL(T)	9	6.4%	6.9%	7.4%	7.8%
	Allied Other	5	3.6%	3.8%	4.1%	4.3%
	Enemy	0	0%

[math]\displaystyle{ \text{Base}_\text{attack} }[/math] is the Value used by each type of Cut-in:

[math]\displaystyle{ \text{Base}_\text{attack} }[/math]	Value	% per Base Value
Destroyer Torpedo-Radar-Lookout	140	0.71%
Gun Cut-in	140	0.71%
Mixed Gun Cut-in	130	0.77%
Destroyer Gun-Torpedo-Radar	115	0.87%
Torpedo Cut-in	122	0.82%
Destroyer Torpedo-Torpedo-Lookout	125	0.8%
Destroyer Drum-Torpedo-Lookout	122	0.82%
Mixed Torpedo Cut-in	115	0.87%
Submarine Radar	105	0.95%
Submarine Torpedo	110	0.91%

Notes:

• Due to the formula's parameters, the effect of over 51 is negligible due to diminishing returns, thus going above such value is generally discouraged.
• The formula used above was datamined from KanColle Kai and is corroborated by test results in the browser version.