For each head, you can deal 30 more damage
See the singles buying guide High-value Charizard cards attract fakes
Blue, Loyal Raptor Compy Swarm Ellie and Alan, Paleontologists Grim Giganotosaurus Henry Wu, InGen Geneticist Ian Malcolm, Chaotician Indominus Rex, Alpha Indoraptor, the Perfect Hybrid Owen Grady, Raptor Trainer Permission Denied Ravenous Tyrannosaurus Swooping Pteranodon Dino DNA Plains Plains Island Island Swamp Swamp Mountain Mountain Forest Forest Command Tower Command Tower
But the property whenever it dies, draw a card effect stays on the card until it dies
I was a bit surprised by quite how effective the Grey Merchant is, initially intending it to reside in the C cube only to come out for quirky decks but it seems comfortably powerful enough for a main cube slot