Armored Guardian is a rare Creature — Cat Soldier card from Invasion (INV), collector number 230. Current market price: $0.36 (foil $8.23), TCGplayer market prices via Scryfall.
{1}{W}{W}: Target creature you control gains protection from the color of your choice until end of turn. {1}{U}{U}: This creature gains shroud until end of turn. (It can't be the target of spells or abilities.)