Erinaio, Leader of Armies

Player (Creatures blocked by Erinaio gain trample until end of turn. Erinaio cannot be removed from the battlefield.)
Battalion - Whenever Erinaio and at least two other creatures attack, Erinaio gets +2/+2 until end of turn and other attacking creatures you control get +1/+1 until end of turn.
Mana Pool - {r} or {w}