The Final Burden

Enchant creature you control
Enchanted creature gets -13/-13 and has "When this creature deals combat damage to a player, that player loses the game."
"Ages ago, a small, frail man was swept by the tide of war, buried deep below the surface, doomed to lay for eons. But as he began to writhe for freedom, he grew stronger in his slow escape. When he finally broke from the unearthly bonds, he was the mightiest man alive.