One of many features Hack/Mine introduces to Minecraft is a stat system. It currently includes Strength, Agility (now defunct), Dexterity, Intelligence, Wisdom, and Fortitude. While the mechanics are mostly in place, the balance still has a long way to go (That's what alphas are for!). These stats determine what your limits will be, as well what kind of character you can evolve into. Each time you level up, you will be able to add 5 Stat Points (Spending Points) to your skills. If you want to be a tank, you would focus on your Fortitude and put a little investment into Dexterity. If you want to be an assassin, you would foucus on Strength and Agility (currently defunct). If you want to be a ranger, you would focus on your Dexterity. If you wanted to be a wizard, you would focus on Intelligence and Wisdom. For more information on Skills, look below.
StrengthEditStrength is the main stat for any warrior. It adds more damage to your base damage. As a result, you will hit harder. You can see your base damage by having your bare hand out (no weapon or item) and looking below your fortitude stat. It will appear as DMG 3-4 for example.
And it is also one of the best way to get crits!
AgilityEditAgility is currently defunct. Or in other words, not in use.
DexterityEditDexterity is the base stat for any Archer class fighter, although it is very useful in other classes. As in the game states, it makes an archers arrows hit harder, or cause more damage. But besides that, it adds two other effects. It adds an effect of faster attack speed. So you can fire faster, or swing faster. Mages can fire more bolts, while Warriors can swing more. It also increases your chance of getting a critical hit. Also, each point put into Dexterity improves defense by one point.
Intelligence EditIntelligence is used primarily by Mages. In fact, it helps only anyone with a wand. It adds more damage to their magical attacks. It also allows your spells to be more potent and fire more projectiles.
WisdomEditWisdom is used to increase your total mana. Mana is used to cast spells. All spells use mana.
Mana is also used to use wands all mages start out with one wand, each Wisdom point results in 10 more Mana.
FortitudeEditFortitude is simply used to increase your health. More health equals the more damage you can take. So beware of tankers!
Warriors gain 12 HP per Fortitude, Mages 7 HP, and Rangers 10 HP.