I played it, for a long time, from the "all paying" to the "hey see that, we have 1% of the game free", I've seen a lot of changes in the classes and gameplay (basically, all classes but archers got nerfed before they understood they overdid it).
History : You are sent to seek the dragon's eggs (called Dofus) which are here and there in the world. You can chose between 14 or 15 classes (despise the world is named World of 12.. they added some after) which all have their specificities : range, dolls, time magic..
Gameplay : The world is divided in a lot of minimaps, with groups of foes. The fights are turn-based, the quickest character begins, then the opposide side, then again the 1st caracter's side... If you begin for example, the turns are : you foe1 ally1 foe2 etc
Teams of 8 max, once a player die his turn is automatically passed (so double turn for ennemy), and the pets take action right after you. Also, the turn is ruled by your movement points and action points. You have 3 MP and 6 AP base, and can gain some with items.
Also, the skills are divided in 5 elemental attributes : fire (intelligence), wind (agility), water (luck) , earth and neutral (both strengh). The classes also have elemental affinities, so you can build a unusual character tpe if you want (will be very hard for a first character though)
I think I resumed it pretty well..
Ah also : the community is really childish and it's hard not to be spammed by RMT.