Holo

A holo (short for holofoil) is a card whose illustration window is printed on holographic foil, so the artwork shimmers as you tilt it. In most sets, holo versions of a card sit at the Rare slot or above, while the rest of the card face stays matte.

Collectors care because the holo version of a card is usually scarcer and more sought-after than its non-holo print. The foil pattern has changed across eras — cosmos swirls, galaxy stars, cracked ice, water-web patterns — and pattern differences can help identify when and where a card was printed. Do not confuse it with a reverse holo, where everything except the artwork is foil.