Aethershield Artificer is a uncommon Creature — Dwarf Artificer card from Core Set 2019 (M19), collector number 2. Current market price: $0.26 (foil $0.20), TCGplayer market prices via Scryfall.
At the beginning of combat on your turn, target artifact creature you control gets +2/+2 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)