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HeathcliffKurokumo Clan Wakashu
He gains two separate buffs depending on his allies: 
Dark Cloud Blade if there's at least one other Kurokumo identity on the field and 
Battle Ready if 3 or more Kurokumo allies have died.
His counter gains 1 coin reuse each if he has Dark Cloud Blade or Battle Ready, turning it from a 1 coin to a 3 coin skill. Using his S3 also gives him 
Cumulus Wall on the next turn which forces both reuses to happen once.
Use him with [Ishmael] Kurokumo Clan Captain since she gives the counter 
Unbreakable Coin and +4 Final Power on Clash Lose.
If his passive is active (3 
Res.), he attacks enemies that attacks his allies. If the ally drops below 25% HP or dies, he uses his counter (once per ally, up to 2 times per turn). This version of the counter doesn't count as a defense skill so it doesn't benefit from 
Defense Power Up, but it can still benefit from Cumulus Wall. If the ally stays above 25% HP, he uses his S1 instead (once per turn).
Dark Cloud Blade gives him 
Slash Power Up and bonus 
Bleed application.
Each Kurokumo ally that dies gives him a Slash Power Up for the rest of the fight.
Battle Ready gives him more Slash Power Up, some 
Slash DMG Up and more bonus Bleed application
All his attack skills also him Defense Power Up for a turn making his counter stronger.
3 +4
62 (+2)Clash: 3-16Damage: 6-28.6Atk Weight:Bleed on target (max 2)
[On Use] Gain 2 Defense Power Up next turn (once per turn)
BleedBleed
Offense Level Down
4 +663 (+3)Clash: 5-22Damage: 8-37.4Atk Weight:Bleed on target (max 2)
[On Use] Gain 1 Defense Power Up next turn (once per turn)Bleed
Slash FragilityBleed Count
Attack Power Down (2 times per turn)
5 +465 (+5)Clash: 6-25Damage: 21-88.2Atk Weight:Bleed on target (max 2)
[Combat Start] Gain 1 Cumulus Wall next turn
[On Use] Gain 1 Defense Power Up next turn (once per turn)
[Clash Win] Gain 1 Dark Cloud Blade next turn (once per turn)BleedSlash FragilityBleed
4 +564 (+4)Clash: 5-11Damage: 24-94.5Atk Weight:Unbreakable Coins
- Final Power +4 to this Skill upon Clash Lose
Deal +10% damage for every type of negative effect on target (max 100%)
[On Use] If this unit has Cumulus Wall, unconditionally activate all Reuse effects on this Skill's CoinsBleedDark Cloud Blade, Reuse Coin once (once per Skill)Battle Ready, Reuse Coin once (once per Skill)Slash Power Up for this Encounter
When 3 or more Kurokumo Clan allies are defeated, gain Battle Ready for this Encounter x3Dark Cloud Blade (max 1)
Against enemies that, in this turn, used Defense Skills or were at max HP before attacking: deal +10% damage
If an enemy attacked another ally with a Skill and dealt damage this turn: use an Unopposed Attack against the attacker with Skill 1 (once per turn)
If the enemy killed another ally, or if the said ally's HP is at less than 25% after the enemy's attack, use an Unopposed Attack against the attacker with x5