Nakarkos, Skeleton Dragon

Bone armor - Whenever a creature leaves a graveyard, Nakarkos gets a +1/+1 counter.

Whenever a creature is sent to your graveyard from anywhere, you may pay {2} and exile it, create a 2/2 Skull Tentacle creature token with all the abilities of exiled creature.

Dragon laser - remove any number of +1/+1 counters from Nakarkos, deal that amount of damage to target creature or planeswalker controlled by an opponent. If that target would die, exile it instead and draw a card.