A very efficient and controllable board-sweeper, Earthquake can generate awesome card advantage. The best part about Earthquake is that it's not completely indiscriminate. You can decide how much you want to shake up the board, killing off your opponent's creatures, but leaving your high toughness creatures - like Earth Elemental alive. You can also design your deck around this little gem. Fill your deck with flying creatures like Granite Gargoyle, Goblin Balloon Brigade, and Dragon Whelp who won't feel the effects of the devastating quake, or run creatures with protection from red. Consider protecting yourself from the effects by running Circle of Protection: Red. Make Earthquake even more devastating by running it with Mana Flare, and put the hurt on your opponent's flyers by running Earthbind.