Caller of the Pack is a uncommon Creature — Beast card from Commander 2015 (C15), collector number 34. Current market price: $1.43, TCGplayer market prices via Scryfall.
Trample Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)