Honestly, is not really necessary to get a creature that can attack in the same turn as you cast worldfire. After casting it, both players exile everything and get their lifes set to 1. No one can cast anything, no one can gutshot you, all depends on what your oponent draw and unless your oponent cast a menmite, they are out of options. You can safely wait one turn and attack in the next one with the creature you exiled I'm working on something, mainly UG http://www.mtgvault.com/ViewDeck.aspx?DeckID=379958
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