General Grevious, Tactician

At the beginning of each end step amass
Droids 1. (Put a +1/+1 counter on an Army you control. It's also a Artifact Robot. If you don't control an army, create a 0/0 colorless Droid Artifact Robot creature token first.)
When one or more cards leave your graveyard, amass Droids 1.

Escape—{3}{b/r}, Exile 4 other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)