Ib Halfheart, Goblin Tactician is a rare Legendary Creature — Goblin Advisor card from Time Spiral (TSP), collector number 163. Current market price: $0.82 (foil $22.53), TCGplayer market prices via Scryfall.
Whenever another Goblin you control becomes blocked, sacrifice it. If you do, it deals 4 damage to each creature blocking it. Sacrifice two Mountains: Create two 1/1 red Goblin creature tokens.