Zhonya's OP.
I said the same thing when I first saw Tankali, no use questioning it.
Well his passive dmg scales with .5 AP, and his w heal does as well, so the ap part helps him. Plus the active, plus armour, so I can see it.
1W 0L is 100%
it's Kha'Zix, as long as it has stats on it you can probably do well with it.