Omarthis, Ghostfire Initiate wants as many counters as he can get, and fortunately for us, he's not the only colorless card that cares about a copious collection of counters
Pyreswipe Hawk: Another of the new cards, Pyreswipe Hawk gets bigger from your big artifacts, and if you cast big spells with it in play, you can swipe your opponents artifacts
If they choose to use three creatures, that's three blockers that are taken care of to allow your other creatures to get in for damage
note As quoth Gandalf, Shadowfax is literally showing us the meaning of haste
It appears that Affinity does not have any MTG cards that benefit from the keyword itself
Build up your Energy counters quickly over two turns while delaying your opponent, before spending the Energy to play a powerful card for free