Although i guess this was a joke thread, i have, and have seen others, absolutely wreck face with zilean. if you have a teammate that can harass well, you can hide in the bushes, and bomb -> rewind -> bomb somebody at level 2 for well over 1/2 their life. With an early game mejai, by level 6 you can double bomb kill most champs from full easily. Toss in a haste + ult and a flash afterward, you can do anything, tower dive 5v1's and come out with at least 1 kill (2+ if they don't spread out) and no death.
3rd time ever playing him i went 16/2 (had awesome taric laning partner harrassing and stunning)