Arcanox

Arcanox was a fantasy themed blend of collectible cards, tower defense and combat strategy MMO released in 2015. You collected and crafted cards, built your castle, attacked castles of other players, stole gold, joined/created guilds and competed against other guilds in the dungeons. The dungeons were randomly generated levels which had to be solved with the least number of cards to get a high score. The game server was shutdown in October 2020.