Red Cavalry Bandleader

Soldiers and Knights you control have +1/+0 and menace.
Whenever Red Cavalry Bandleader attacks, if you control no other creatures, it gains +3/+0 until end of turn.
When Red Cavalry Bandleader dies, you may exile it. If you do, reveal cards from the top of your library until you reveal a Soldier or Knight creature card, put it into your hand, then shuffle your library.
"Cavalry, attack!"