Dexterity

From the KF manual

The more skilled you are, the better you can handle your shield and armor.

What's the use?

For each point of skill you get X points bonus on damage defense. (Unfortunately, there is probably a formula behind it, which you cannot see at first sight)

Example: a skill of 12 gives an additional 0.24 points. If you have a basic damage defense (through armor and/or shield) of 1.00 to 3.00, the total defense is 1.24 to 3.24 points. These points are deducted directly from the damage of the opponent in combat.

'Attention: without worn armour you will not get a bonus either.

Therefore, most players who Two-handed and therefore no Armor Skill and carry also this point.