How are sticker cards different from trading cards?

Pokémon's sticker lines, Amada's in Japan and Merlin's in Europe, look like small cards and are catalogued like cards, but they obey different rules in every way that matters to a collector. Start with purpose: a TCG card is a game piece that happens to be collected; a sticker card is a picture that happens to be carried on card stock until the moment it is peeled and placed in an album. Merlin's own reference works state the consequence flatly: remove the sticker from its backing and it stops being a card. A TCG card played a thousand times is a played card. A sticker stuck once is a used sticker, forever.

The formats and numbers differ too. Amada seals are 50mm squares numbered in one long Retsuden sequence that climbs across sets and years; Merlin stickers are numbered within each series, Pokédex order first. Neither uses the TCG's set symbols or rarity marks; rarity lives in the finishes, plain, prism, gold, and in distribution quirks like stickers sold only with an album case. And the shops differ: TCG cards came from game and hobby stores in booster packs, while stickers came from candy shops, kuji lottery hangers and newsagents, priced for pocket money, two Amada seals for about twenty yen.

For identification, work from the back. A sticker card's reverse is backing paper or a printed card back carrying the maker's marks, Amada's red name or Ensky's green one in Japan, Merlin's trademark year in Europe, never the TCG's Poké Ball card back. Data lives there too: Amada printed the Pokémon's data on the backing, so the back is half the document. Read both sides before you name any sticker, and never peel to check.