Ephemeral Shields is a common Instant card from March of the Machine Commander (MOC), collector number 184. Current market price: $0.31, TCGplayer market prices via Scryfall.
Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.) Target creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)