Hitting a naturally spawned mob yields experience according to the damage you deal to the mob multiplied by its XP multiplier.
Iron Arm increases the damage dealt when hitting mobs or players with your fists.
Arrow Deflect is a passive ability that gives you a chance to deflect arrows shot by Skeletons or other players. The arrow will fall harmlessly to the ground.
Iron Grip is a passive ability that counters disarm. As your unarmed level increases, the chance of preventing a disarm increases.
This passive ability allows players to disarm other players, causing the target's equipped item to fall to the ground.
Beserk is an active ability that is activated by right-clicking. While in Beserk mode, you deal 50% more damage and you can break weak materials instantly, such as Dirt and Grass.
To read this guide on the server type /unarmed ? [page]