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
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
For just general value copying it seems underwhelming by the time you cast it, and have the 2 mana ready to copy the effect
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
Instead, tap it, remove all damage from it, and remove it from combat
A fairly mediocre green card for a fringe archetype just jumped a mind-blowing 1600% in price, shooting from around 25 cents to well over $4