Mardu Dragonslayers

Belligerent (When this creature enters the battlefield, you may discard any number of cards. If you do, it enters with that many +1/+1 counters on it.)
At the beginning of your upkeep, destroy target Dragon creature. If you can't, tap Mardu Dragonslayers and it deals 3 damage to you.
{b}, {ut}: Put target creature from a graveyard onto the battlefield under target opponent's control.