Tyvar's Stand is a uncommon Instant card from Phyrexia: All Will Be One (ONE), collector number 190. Current market price: $1.98 (foil $1.92), TCGplayer market prices via Scryfall.
Target creature you control gets +X/+X and gains hexproof and indestructible until end of turn. (It can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)