It's Hit Chance, but also Defense Chance. So the higher your skill the better chance you have to hit and avoid being hit. Here's the formula straight from Stratics:
Hit Chance% = ( ( [Attacker's Combat Ability + 20] * [100% + Attacker's Hit Chance Increase] ) divided by
( [Defender's Combat Ability + 20] * [100% + Defender's Defense Chance Increase] * 2 ) ) * 100
Minimum hit Chance% is 2% at all times.
I found this from Stratics main UO page (
http://uo.stratics.com) in the left column under "Combat". This formula also shows how DCI and HCI are factored into the equation.
Is 120 significant? The best example would be show your chance to hit a swordsman with 120 skill if you only have 100 with no DCI or HCI on either side:
Your chance to hit would be...
((100 + 20) * (1.00)) / ((120 +20) * 1 *2) * 100
120 / (140 * 2) * 100
120 / 280 * 100
You'd have a
42.85% chance to hit your enemy
Your enemy's chance to hit you would be:
((120 + 20) * (1.00)) / ((100 +20) * 1 *2) * 100
140 / 240 *100
Your enemy would have a
58.3% chance to hit you
That seems kind of significant to me.
