I think Sai has a passive( he has 5 elements) and can avoid that additional 20% damage due to element. Otherwise as S81-Avacyn mentioned, ninja tools can reduce the damage from one particular element by 1 or 2%, rest of the damge you willl have to take, esp with people like gnw 10-10 who does 5 element damage.

DOES IT COUNT AS A DEBUFF?

That's an interesting question actually as I am unsure as to what debuff is. Normally we refer to poisoning, igntion, chaose etc as debuffs and these things can be healed off with 100% assurance with a healing mystery. But elemental damage cant be avoided by healing. So maybe its not a debuff, if the definition of debuff is anything that cant be healed off. Debuff could also mean anything that which negatively affects the team. Like blindness wastes your standard attack, chaos messes up your player etc. In that manner its a debuff, because it affects you team negatively. I have been thinking about it. On the other hand buffs are percentage boosts to attributes for certain rounds. based on that definition of buffs, anything that makes you take more damage(means lesser defense or resistance, not really a reduction of these stats, but you are anyway taking more damage, so can be equivalent to a percentage reduction of defense or resistance). In that manner elemental damage could be a debuff..Honestly I dont know. Wish I could know it. But it doesnt matter, At the end of the day, you have to take that damage.

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