Loki, God of Lies

Hexproof, indestructible
Loki, God of Lies cannot be sacrificed. Tap an untapped creature you control: Put a lie counter on Loki, God of Lies, then destroy target creature. At the beginning of each end step, if there are more than X lie counters on Loki, God of Lies, where X is the amount of mana spent to cast it, exile it with a snake counter on it.
At last, all his lies had caught up to him...