: Destroy target creature if it shares a color with the most common color among all permanents or a color tied for most common. A creature destroyed this way can't be regenerated.

Wormfang Crab can't be blocked.
When Wormfang Crab enters the battlefield, an opponent chooses a permanent you control other than Wormfang Crab and exiles it.
When Wormfang Crab leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Whenever another creature enters the battlefield, you lose 1 life.