Just a Li'l Guy is a rare Instant card from Unknown Event (UNK), collector number RG11a. Current market price: $25.00, TCGplayer market prices via Scryfall.
Target creature gains hexproof and indestructible until end of turn. That creature is 1/1 until end of turn and can't be anything other than 1/1 until end of turn. (No matter what happens to it, it'll still be a 1/1.)