Delina, Wild Mage is a rare Legendary Creature — Elf Shaman card from Secret Lair Drop (SLD), collector number 2770. Current market price: $12.17 (foil $5.19), TCGplayer market prices via Scryfall.
Whenever Delina attacks, choose target creature you control, then roll a d20. 1—14 | Create a tapped and attacking token that's a copy of that creature, except it's not legendary and it has "At end of combat, exile this token." 15—20 | Create one of those tokens. You may roll again.