The Pokémon TCG hides Unown in the background art of 12 cards. The cameos sit across 2001–2021, with Milky Isobe, Nakaoka and Hideaki Hakozaki responsible for several of them.
These cards feature indeterminate, symbols, ancient and stone in their background art, illustrated by artists like Milky Isobe, Nakaoka and Hideaki Hakozaki.