Chromatic Armor is a rare Enchantment — Aura card from Ice Age (ICE), collector number 283. Current market price: $0.97, TCGplayer market prices via Scryfall.
Enchant creature As this Aura enters, choose a color. This Aura enters with a sleight counter on it. Prevent all damage that would be dealt to enchanted creature by sources of the last chosen color. {X}: Put a sleight counter on this Aura and choose a color. X is the number of sleight counters on this Aura.