Take Up the Shield is a common Instant card from Outlaws of Thunder Junction (OTJ), collector number 34. Current market price: $0.19 (foil $0.22), TCGplayer market prices via Scryfall.
Put a +1/+1 counter on target creature. It gains lifelink and indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)