Abby, Merciless Soldier is a mythic Legendary Creature — Human Survivor card from Secret Lair Drop (SLD), collector number 2202. Current market price: $1.53, TCGplayer market prices via Scryfall.
When you cast this spell, create a number of 1/1 black Fungus Zombie creature tokens named Cordyceps Infected equal to the amount of mana spent to cast it. Abby enters under the control of an opponent of your choice. Partner—Survivors (You can have two commanders if both have this ability.)