So, a completely new players enters the game, they will be eventually introduced to the mechanics, they will know the AIs, Colosseum and Arena on the first day or couple of days of playing. What will keep them interested?
The game must offer different 'goals' the players should aim for. This is probably the place to discuss about that.
The most obvious goal on playing the game is getting a full collection. The tools to do that are already made.
Another goal that cg commented and I expanded a bit is on the portraits, or avatars. These are untradeable collectible things that the player show their opponents when starting a PvP match and they will be won by getting achievements, which will be starting from the most basic stuff to beating quests and making particularly hard challenges like winning games with certain conditions. This goal probably includes 'completing quests' in it, as the quests will be one of the sources for portraits.
What else can the game offer to get the players interested in it and prevent them from quitting after a week?
