Moshi Monsters Mash Up is a series of trading cards published by Topps Europe, launched in the United Kingdom in June 2010 as a physical extension of the Moshi Monsters online browser game developed by Mind Candy. The Moshi Monsters franchise was a phenomenon in British children's entertainment, at its peak reaching approximately half of UK children aged six to twelve, and it sold an estimated 170 million trading cards across all formats during its commercial run. The Mash Up game is modelled on the Top Trumps format: each card carries two numerical values, and players choose one to compare against their opponent's card. Series 1 comprised 90 base cards and 18 puzzle cards. Five numbered series were released overall: Series 1 (Moshi Monsters), Series 2 (Super Moshis, 2011), Series 3 (Code Breakers), Series 4 (Moshling Madness), and Series 5 (Party). Each pack contained five trading cards and one redemption code card for in-game virtual items. Cards came in normal, foil, rainbow foil, and code card variants. UK and US packs differed slightly in pack size and price. The Moshi Monsters online platform closed in December 2019.
Source: moshimonsters.fandom.com/wiki/Moshi_Monsters_Mash_Up_Trading_Cards