RaiderZ is claimed to be truly "classless" but has specific weapon styles that the player can select. After level 10, the player can incorporate skills from the other styles to form a hybrid character. This feature is what makes the job system classless as the player can hybridize styles based on their preferred weapon and play style.
Berserker uses one greatsword to bash the skull of the monsters.
Cleric is a healer, but don't underestimate his fighting capabilities.
Defender will protect you with their shield and murder the monsters with their sword.
Assassin quickly moves in to seek and destroy and then quickly leaves.
If you wonder what class is the stronger, the answer is none. The classes are almost equally powered,with the exception of cleric. Chose the class that feels the most fun to play with. What is the point to wave a weapon you don't like?