Trostani Discordant is a mythic Legendary Creature — Dryad card from Starter Commander Decks (SCD), collector number 253. Current market price: $0.31, TCGplayer market prices via Scryfall.
Other creatures you control get +1/+1. When Trostani enters, create two 1/1 white Soldier creature tokens with lifelink. At the beginning of your end step, each player gains control of all creatures they own.