Guild Wars is described as 'Very successful MMORPG with no monthly fees. PvE and PvP, heavily instantiated. Manageable heroes for your party as well as hero-NPCs. 8-skill-deck and attributes, changeable in every outpost to adjust Skills to play-style, team and preference' and is a role-playing game in the games category. There are more than 50 games similar to Guild Wars for a variety of platforms, including Windows, Linux, Android, Mac and Web-based apps. The best Guild Wars alternative is The Elder Scrolls. It's not free, so if you're looking for a free alternative, you could try The Lord of the Rings Online or Runescape. Other Guild Wars like games are World of Warcraft, The Elder Scrolls Online, EverQuest and Aion.
This is not an MMO but a card game with some very limited MMO like elements.