KMS U-2501

When deployed into a sortie, increases this boat's ASR and AMO by 1; at the start of battle, increases this boat's TRP and RLD by 10.0%. Whenever this boat's torpedoes hit an enemy: 70.0% chance to inflict a special Flooding debuff (takes DMG every 3s based on U-2501's TRP, lasting for 15s); additionally, increases the DMG this boat deals to Flooding enemies by 10.0%. Whenever any other ally in the Submarine Fleet hits an enemy with torpedoes: 70.0% chance to increases this boat's ACC by 1.0% (stacks up to 10 times, lasting until the boat leaves the battle); upon reaching 10 stacks, restores 10.0% of this boat's Max HP.

At the start of battle: if all 3 allied submarines are present, increases this boat's Torpedo Crit Rate by 10.0%. During battle, increases this boat's OXY by 40. 1s after this boat's OXY reaches 0 and she resurfaces, this boat retreats from battle. 5s after the start of battle: launches a Lv.10 special barrage (DMG is based on the skill's level). 15s after starting battle with a fleet that this boat is NOT in: as long as this boat has not been sunk, launches a Lv.10 supporting barrage (DMG is based on the skill's level), revealing all enemy submarines in the area for 8s and reducing the ACC and EVA of all enemies on the field by 10.0% for 8s.

When this boat's OXY reaches 0 and she resurfaces, activates All Out Assault II: U-2501.