ToME Wiki
General Info
Hafted-mastery skill basically does three things.
#1 It increases your max blows per round.
#2 It increases your + to hit and dam.
#3 It increases both your Combat and Weaponmastery skills.
Code-related Information
#1 The amount of increase in blows is skill level divided by 25. So at skill level 25 you receive 1 extra blow per round, and at 50, 2.
#2 The increase of hit and dam is + to hit is your skill level, and + to dam is half your skill level. So at 20 skill you would have +20 to hit and +10 to dam. At skill level 50 you would have +50 to hit and +25 to dam.
#3 Spending 1 skill point on your Hafted-mastery skill adds 0.25 bonus skill points to your Weaponmastery skill and adds 0.07 bonus skill points to your Combat skill.