Deathwing from the new Cataclysm expansion
One other note is that Astral Slide and Astral Drift can also remove those pesky creatures for the turn as well
At the start of the Damage Step, if this card battles a DARK monster: Increase the ATK of this card by 300 points and destroy that monster
The four decks coming back are "Devour for Power" (helmed by The Mimeoplasm), "Built from Scratch" (the Daretti, Scrap Savant deck that I turned into one of my most complicated and broken Commander decks), "Wade into Battle" (with Kalemne, Disciple of Iroas leading the charge), and "Breed Lethality" (with everyone's favorite proliferator, Atraxa, Praetors' Voice)
For maximum value, I like the elf token copy and untap + mass pump, but even if you don't have a great elf in play, the other two options can pull you out from a losing situation