In no particular order, Slayers deal a mix of physical and magical damage at close range but have next to no defensive abilities. Heretics are a combination of priests with more sinister magics, dealing damage and healing as well as inviting a few obious comparisons. Magi (or maguses, if you prefer) are... well, okay, they're kind of obvious. Berzerkers have an errant "z" in their name and focus on dealing out physical damage at the cost of some defense, and Champions wield a weapon and shield to be all but indestructible. The classes seem set to provide a fair mix of the usual "holy trinity" mechanics and PvP skills, so take a look at the official preview to get a clearer picture of what you might want to play once the game goes live.