The longer a game goes on, the more Phyrexian Arena puts you in the lead over your opponents, as youll have access to more options and more resources
Instead, tap it, remove all damage from it, and remove it from combat
Gaea's Blessing (T1, Ext, S, Block) Technically a cantrip, Gaea's Blessing puts your best cards back into your deck (or your opponent's cards into his deck), plus gives you a chance to draw them back
You could, in theory, end up using him as a game-ending play if it takes enough damage from other players, or you could use him in a deck thatll have your own creatures damage him to make him a juggernaut
It is one of the main sources of extreme power that elf decks can call upon outpacing even Rofellos in the elf builds of green ramp