The attribute system is already implemented.
Players convert stamina into an increasing amount of health.
Intellect increases damage done and is the most important stat for mana-using classes.
Strength increase damage and critical chance for some classes.
Strength increase damage and it is the most important stat for mele classes in the damage dealing.
Reduce the incoming damage by X-%
Haste affects the the cast time of spells, and the tick rate of DoT's and HoT's and the attack speed.
Crit changes the percentage of damaging attacks and healing spells that result in a critical strike for generally 150% of the effect