First strike (This creature deals combat damage before creatures without first strike.),
trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
At the beginning of your upkeep, put a -2/-2 counter on Ebon Praetor.
Sacrifice a creature: Remove a -2/-2 counter from Ebon Praetor. If the sacrificed creature was a Thrull, put a +1/+0 counter on Ebon Praetor. Activate only during your upkeep and only once each turn.