Varolz, the Scar-Striped is a rare Legendary Creature — Troll Warrior card from Dragon's Maze (DGM), collector number 112. Current market price: $0.46 (foil $4.73), TCGplayer market prices via Scryfall.
Each creature card in your graveyard has scavenge. The scavenge cost is equal to its mana cost. (Exile a creature card from your graveyard and pay its mana cost: Put a number of +1/+1 counters equal to that card's power on target creature. Scavenge only as a sorcery.) Sacrifice another creature: Regenerate Varolz.