Armadillo Cloak is a common Enchantment — Aura card from Duel Decks: Phyrexia vs. the Coalition (DDE), collector number 58. Current market price: $1.84, TCGplayer market prices via Scryfall.
Enchant creature Enchanted creature gets +2/+2 and has trample. Whenever enchanted creature deals damage, you gain that much life.