Poro King Best (or OPs)
Thus far I've had 2 matches but I really think that my vote goes to:
and

Thus far I've had 2 matches but I really think that my vote goes to:
and

Wukong and Garen get a good word in, too.
Soraka's healing can get pretty disgusting.

There's a reason she has a nearly 70% win rate in ARAM. And the OP champs on Poro King are largely still the top champs for ARAM, though gaining a gap close off the poro toss has helped a few of the top ARAM melee champs move up another notch.
But seriously. Ban or pick Sona. I was perplexed yesterday when she wasn't banned two games in a row. I was even more perplexed when the other team didn't pick her up when she was available. I played Sona both times, and both games only lasted about 11 minutes each.