Elvish Warmaster is a rare Creature — Elf Warrior card from Kaldheim Promos (PKHM), collector number 167p. Current market price: $4.99 (foil $8.85), TCGplayer market prices via Scryfall.
Whenever one or more other Elves you control enter, create a 1/1 green Elf Warrior creature token. This ability triggers only once each turn. {5}{G}{G}: Elves you control get +2/+2 and gain deathtouch until end of turn.