Background
How the card game made its way from Japan to individual countries, and why sets are numbered differently there.
In 1999, Bandai launches its own trading card game in Japan to compete with the internationally booming Pokémon TCG — the Starter Set and Booster Series 1 and 2 initially appear largely consistent. But things are inconsistent from the very start: soon after, the cards begin to differ from country to country, on top of numerous miscuts, rough cut edges, and even varying shades of blue on the card backs within the same set.
Promo cards numbered Mo-01 to Mo-12 are released for the first Digimon movie. The US gets all twelve designs, while Germany only gets eight: five of them keep the Mo- numbering, the remaining three carry a Bo- number instead. Even the look is inconsistent across these eight cards — sometimes square, sometimes rounded corners, sometimes a light blue back, sometimes the usual dark blue one.
After just two booster sets, the German edition is discontinued. In the US, the line continues, but with a completely new — and unpopular with collectors from the start — 3D model design (Booster Series 3 to 6). France initially stays true to the original design and releases one or two more booster sets plus a Mega Pack, but from 2001 it too switches to 3D with the Street Starter series (Jd-125 onward). Even Sweden gets a taste of the old design: the McDonald's Happy Meal promo includes, as St- cards, an English-translated selection from French Booster Series 3. The French 2D originals are among the most expensive and rarest cards in the whole line today — and, being in English, make the Swedish cards sought-after rarities too.
Beyond the main line, there are national quirks too: England gets its own edition, available only through cereal boxes, with the cereal promos (Cp-) featuring English-speaking DigiDestined — similar to the German CD insert promos (Fx-), which also depict the DigiDestined and are still highly sought after today.
Ironically, it's the once-unpopular US 3D boosters whose collector value is exploding today — an effect familiar from the Pokémon world with sets like Skyridge or Aquapolis. Just recently, three unopened boosters from US Series 3, 4 and 5 changed hands for a combined $2,400. Also considered absolute rarities: the Goldramon promo card from the "Digimon Weekend" at Universal Studios (Un-01), and the American Fx- edition of the DigiDestined.