about stackable buffs/debuffs of Iruka, Kushina, Bee, Gamariki, etc...

usually the stack is infinite. Gamariki can reduce resistance to up to 10 times in 10 rounds (proc everyround) and reduce up to 90% resistance (each time reduce 20% res). Kushina can stack infinitely if hit alive, or better, bring the buff forward to the next wave (only works in PvE like Ninja exam)

some buffs/debuff is limited like iruka can buff 5 times max in 1 battle, edo dei scale can only buff him 5 times each round (if 6 units die he only scale 5 times), and edo hashi reduce att/nin (after skilltrial) can only reduce max till 5 times...

If the unit is dead and revived, all the buffs and debuffs will be reset... it's like getting a new life.