Managorger all day and it isn't even close. He rewards well-crafted decks and Trample keeps him extremely relevant. The single G in the cost is great, too.
Champion.. Where do I begin? 1GG for a 2/2 is already dull as nails, and you're probably playing him on T4 so he doesn't die immediately while you belch a land on the board, unless you're ramping into him. Then, every turn that you play a land, he gets harder for aggro/creatures/burn to interact with, while still being easy pickings for non-burn control decks. You want to include more Midrange vs Control incentives? Well, here comes your man. Personally, I have enough difficulty pushing aggro hard enough in my fast environ that I don't care to give green another big stupid creature that is neigh-unkillable in a R-based or creature-centric matchup, but that's me. I get it, Phantom creatures were cool, but they play hell on red and creature aggro, so I suggest anyone who worries about aggro vs green run, not walk, away from Champion as quickly as possible.