- Development Hell: Where the game's booster packs were for a bit, and where the first and only expansion set, Generations, ended up (and remained) after poor sales of the booster packs.
- Troubled Production: Part of the game's failure was the large release gap between the starter set and booster packs. This was completely Marvel's fault, due to delays in drawing new card artwork. By the time the booster packs finally hit the market, they often went straight to clearance because interest had waned so much.
- What Could Have Been: The expansion set Generations would've introduced cards for Iceman, Gambit, Cable, Nightcrawler and the Acolytes Senyaka Cortez and Frenzy. The latter three being left until an expansion set is especially unusual, given their prominence in the game's tie-in comic.
Trivia / X-Men Trading Card Game