The Calamity Vessel

Ward - sacrifice a commander.

First strike, indestructible, reach, trample.

Crew 6, as an additional cost to crew this vehicle sacrifice a legendary creature or planeswalker.

When The Calamity Vessel becomes crewed it gains annihilator X where X is mana value of the card sacrificed to pay the crew cost until end of turn.

Desperation's call was answered.