Imperial Mask is a rare Enchantment card from Future Sight (FUT), collector number 23. Current market price: $0.46 (foil $4.63), TCGplayer market prices via Scryfall.
When this enchantment enters, if it's not a token, each of your teammates creates a token that's a copy of this enchantment. You have hexproof. (You can't be the target of spells or abilities your opponents control.)