Stats

- Wisdom is related to Mana, the more wisdom one has the more mana they will have.

- Intelligence is related to magic damage, the more Intelligence one has the stronger their attacks.

- Strength, on the other hand, relates to how hard one can hit with their weapon. Every weapon has a range of attacks, and due to strength, the damage can increase.

- Vitality is related to Hp. 1 vitality is 10 Hp.

- Stamina, it is a necessary stat to almost all classes. It helps with movement and rate of attacks, Thieves would need high stamina to chain attacks, every physical attack would cost a bit of stamina. So, the more stamina one has the more they can hit or dodge. It would increase by 100 for every level up.

- Defense and Magic resist. They are stats that help resist a percentage of the damage dealt to a character. If I remember correctly. An attack of 1000 damage if it lands on a character with 100-defense only 900 damage will be dealt to the character. The same goes for magic resist.

- Rage is fixed at 100, and cannot be increased, at least not normally. There are some weapons that add a small portion of rage points. And they are really rare. Rage can steadily increase with each attack or damage taken. And it increases over time if one enters combat state. A warrior class needs not mana to cast their skills, but they need rage points and stamina. Even if their skills are not on cooldown without sufficient rage points they can't cast any warrior skills. Which is quite inconvenient.

Reference

 * Chapter 2
 * Chapter 4
 * Chapter 7