Sorry about that, I guess the best way to describe this game is...
Start with Double Dragon, Streets of Rage, Battletoads or any other brawler type before the PS1 days. Add different class types: Fighter, mage, brawler, summoner etc, you can get & level up different skills and choose different "awakenings". Think FF1 character upgrade mechanics sort of. There are alot of quests, WoW style with the ! & ?'s for quest starts & turn ins. All the while, you go through different dungeons by yourself or with a party of yourself & 3 other players.
It's free to play, describing it is a bit tough, I feel it's easier to get a feel for the game by playing it or watching a Let's Play.