Horde

At the beginning of your upkeep, create a 1/1 black Minion creature token with "This creature can't block."
Sacrifice a Minion: Add {b} or {g} to your mana pool.
Whenever a Minion dies, put a +1/+1 counter on a Minion you control.
If you control 10 or more Minions, Minions you control gain trample.