• The flagship must be a Submarine Tender (AS) at Lv 30+,
  • She must not be more than moderately damaged (中破).
• The 2nd and 3rd ships must be Submarines (SS) or Aircraft Carrying Submarines (SSV) and not evacuated via SFFCF,
  • The 4th ship may optionally be a SS(V), but does not affect the above requirement,
  • At least two SS(V) among the 2nd, 3rd, and 4th ships must not be more than lightly damaged (小破),
  • If all 3 ships are SS(V), the 2nd and 4th ones will attack; if one of the two is moderately damaged (中破), the 3rd one will attack instead.^[1]
• The fleet must be a single fleet or a Striking Force Fleet,
• The formation needs to be either Echelon or Line Abreast,
• At least one Submarine Supply Material must be available in the inventory.

• Two SS(V) will launch torpedo strikes.
• The attack power of each strike is postcapped and unaffected by formation, engagement, or damage cap.
• A rough damage formula per Submarine attack is:

[math]\displaystyle{ \text{DMG}_\text{day} = \text{TP} \times ( 1.2 + 0.04 \times \sqrt{LV} ) }[/math] [math]\displaystyle{ \text{DMG}_\text{night} = ( \text{FP + TP} ) \times ( 1.2 + 0.04 \times \sqrt{LV} ) }[/math]

With

• [math]\displaystyle{ \text{DMG} }[/math] the damage result for day and night battle respectively,
• [math]\displaystyle{ \text{FP} }[/math] the submarine's Firepower stat,
• [math]\displaystyle{ \text{TP} }[/math] the submarine's Torpedo stat,
• [math]\displaystyle{ \text{LV} }[/math] the submarine's Level.
  • [math]\displaystyle{ 1.2 + 0.04 \times \sqrt{LV} = 1.6 }[/math] at Lv 100.

The number of attacks per Touch ranges from 2 to 4.

• Each submarine will trough either 1 or 2 torpedo strikes.
  • Only Lv 75+ submarines can trigger 2 strikes,
  • If a Lv 75+ submarine does not carry any Submarine Radar, it rolls between 1 and 2 strikes randomly (exact rate unclear yet),
  • If a Lv 75+ submarine does carry any Submarine Radar, it is guaranteed to roll 2 strikes.

One Submarine Supply Material will be consumed for EACH battle the Touch triggers in.

• If the Touch triggers twice in a battle, only a single will be consumed for this battle.
• If the Touch triggers in multiple nodes, one will be consumed for each node it is triggered.

It does not consume any extra ammo. If the game is refreshed before the battle ends, then no material will be consumed even if the touch triggered.

Trigger rate is affected by the Level and luck stat of the participating ships^[1].

• Submarine Radars affect the trigger rate, each increasing the trigger rate by about 10 %^[2].

It has a chance to trigger every time the AS takes a turn at shelling.

• It can trigger in both day and night for the same battle.
• It can only trigger once during day battle.
• If it fails to trigger during the day battle, there is still a chance to trigger it in the follow-up night battle.
• If all enemies sunk, then touch stops early.

The attack order is always (where amo,g the attacking submarines, 1 is upper one and 2 is lower one):

• 1-1-2-2 for 4 attacks,
• 1-1-2 or 1-2-2 for 3 attacks,
• 1-2 for 2 attacks.
  • If touch stops early, then attacks can be just 1-1
  • Also note that the actual order may be different from client animation of who shoots torpedoes, which always assigns attackers alternately like 1-2-1-2 or 1-2-1 or 1-2, so you may mismatch the real attack.

The touch can be activated multiple times per sortie.

When attacking a fleet, the usual Targeting rules apply.

• The torpedoes fired target ships independently,
• When facing a Combined Fleet, if any ship is present in the escort fleet on day battle, then all torpedoes will be fired to the escort fleet.

Regular
Taigei Special Attack Taigei Special Attack Damaged Jingei Special Attack Jingei Special Attack Damaged Jingei Special Attack Kai Jingei Special Attack Kai Damaged Chougei Special Attack Chougei Special Attack Damaged Chougei Special Attack Kai Chougei Special Attack Kai Damaged Heian Maru Special Attack Heian Maru Special Attack Damaged Heian Maru Special Attack Kai Heian Maru Special Attack Kai Damaged
Seasonal
Taigei Summer 2021 Special Attack Taigei Summer 2021 Special Attack Damaged Jingei Summer 2021 Special Attack Damaged Jingei Summer 2021 Special Attack Chougei Summer 2022 Special Attack Chougei Summer 2022 Special Attack Damaged Heian Maru Summer 2024 Heian Maru Summer 2024 Damaged Heian Maru Kai Summer 2024 Heian Maru Kai Summer 2024 Damaged Special Attack Summer bis 2024 Special Attack Summer bis 2024 Damaged Special Attack Kai Summer bis 2024 Special Attack Kai Summer bis 2024 Damaged