Souvenir T-Shirt is a rare Artifact — Equipment card from Unfinity (UNF), collector number 478. Current market price: — (foil $0.24), TCGplayer market prices via Scryfall.
Gear Up, sponsored by Wizards of the Coast — As this Equipment enters, roll two six-sided dice. For each Magic-branded item you're wearing, roll an additional six-sided die. Choose two of those results. Equipped creature gets +X/+Y, where X is the first chosen result and Y is the second. Equip {4}