Night Battle Breakdown

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

If your fleet pursues the enemy into Night Battle (夜戦, yasen), or you enter a special Node such as a Night Node or a Night to Day Node, your 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:

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 equipment that influence the battle in such ways are Searchlight, Large Searchlight, Star Shell and Night Scout.

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 Requirement(s)
 Star Shell 
  • Increases the   of your fleet.
  • Increases the cut-in rate of your fleet.
  • Greatly decreases the cut-in rate of the enemy fleet.
  • Ship must have at least 5  
  • Trigger rate is 70% per ship equipped with a Star Shell. By fleet order, if the first ship's 70% fails, the next ship's 70% is rolled, etc.
 Searchlight 

 Large Searchlight 

  • Greatly increases the   of your fleet.
  • Greatly increases the cut-in rate of your fleet.
  • Decreases the cut-in rate of the enemy fleet.
  • The equipping ship has its evasion sharply reduced, and is targeted more often.
  • Ship must have at least 2  
  • Trigger rate is 100%
 Skilled Lookouts 
  • Increases the cut-in rate of the ship equipped with it.
  • None
 Night Recon 
  • Increases the   of your fleet.
  • Increases the   stat of your entire fleet by +5.
  • Increases the critical hit rate of your fleet.
  • The recon cannot be equipped on a slot of size 0.
  • The success rate is dependent on the level of the ship it is equipped on.
  • Trigger rate is [math]\displaystyle{ \text{Trigger %} = \left[ \sqrt{3 \times \text{Level}} \right] \times 4 }[/math]
  • If there are multiple night scouts in your fleet, each will have a chance to trigger.
  • If the Night Battle was preceded by a day battle:
    • The Air State must be AD, AS or AS+.
    • The Air State must be AD, AP, AS or AS+ in PvP.

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  .
    • If the enemy is unaffected by torpedoes, such as installations, only   is used instead.
  • Heavily damaged (大破) (Taiha?) and sunk ships are unable to participate in battle.
  • All types of Aircraft Carriers 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. This makes it not possible to sink a submarine during Night Battle.
    • This rule is void if the player fleet is a Combined Fleet.
    • Friend Fleet also ignores this rule and may damage submarines
  • Ships with 0   +   stats are unable to participate in battle.
    • Currently, this is only observable against the Wa-Class Transport Ship.
  • All heavy cruisers gain +5  
  • Heavy cruisers equipped with IJN 20.3 cm guns will gain an accuracy and evasion bonus. Please see Gun Fit Bonuses for more details.
  • Destroyers equipped with Skilled Lookouts and a Radar will gain bonus evasion. The exact amount is unknown.
 
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 form.

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

2. Swordfish Night Attack

  • This is just limited to Ark Royal  (all 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.
  • There is a critical multiplier bonus from plane proficiency.
  • May be set up to activate Double Attacks and Cut-Ins.

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.
  • 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 you have no bombers.
  • 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 in 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-in you would be rolling 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.

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 damages 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.

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
Destroyer Cut-ins     1.3 2/1
With 12.7cm Model D Kai 2  1.625 2/1
With 12.7cm Model D Kai 3  1.706 2/1
    Synergy with evasion bonus 1.2 2/1
With 12.7cm Model D Kai 2  1.5 2/1
With 12.7cm Model D Kai 3  1.575 2/1
    Requires TS Lookout  1.5 2/1
    Requires TS Lookout  1.3 2/1
Carrier Cut-ins [1]    

  =     

1.25 1
   1.2 1
   
OR
   
1.2 1
     1.18 1
  • By using a second 12.7cm Model D Kai 2  when performing a Destroyer Cut-in, an additional bonus of 1.125x is applied multiplicatively to the attack. This setup can only be deployed on Tashkent Kai .
  • Starting from 2021-05-08 (Spring 2021 Event), Destroyer Cut-ins have a chance to deal 2 separate hits rather than 1 if the attacking Destroyer is level 80 or higher:
Attack Type Chance for 2 Hits[2][3]
    65%
    50%
    87.5%
    ~55%?

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 meet the prerequisites. If this roll fails, the ship will perform a Single Attack.

Attack Type Prerequisites Notes Pre-cap
Damage
Modifier
Hits
Gun Cut-in     + Any on the remaining slots 2 1
Mixed Gun Cut-in     No additional   1.75 1
Submarine Cut-ins    With Late Model Bow Torpedoes ONLY 1.75 2
   1.6 2
Torpedo Cut-in    + Any on the remaining slots 1.5 2
Mixed Torpedo Cut-in    Additional    allowed 1.3 2
Double Attack    No additional     1.2 2
   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
Health Moderate damage
(中破 Chuuha)
18 12.9% 13.8% 14.8% 15.7%
Any other health state 0
Searchlight  Allied 7 5% 5.4% 5.7% 6.1%
Enemy -5 -3.6% -3.8% -4.1% -4.3%
Large Searchlight  Allied ?
Enemy -?
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
Torpedo Squadron Skilled Lookouts  Allied DD/CL(T) 9[1] 6.4% 6.9% 7.4% 7.8%
Allied Other 5[2] 3.6% 3.8% 4.1% 4.3%
Enemy 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[3] 0.71%
Gun Cut-in 140 0.71%
Mixed Gun Cut-in 130 0.77%
Destroyer Gun-Torpedo-Radar 115[4] 0.87%
Torpedo Cut-in 122 0.82%
Destroyer Torpedo-Lookout-Torpedo 125[5][6] 0.8%
Destroyer Torpedo-Lookout-Drum 122[7] 0.82%
Mixed Torpedo Cut-in 115 0.87%
Submarine Radar 105[8][9] 0.95%
Submarine Torpedo 110[10] 0.91%

Additional 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.