well this is how i mastered my will and got it to max i did this after i completed the game.
The spell u will need is summon and physical shield if u get hit alot and lots of will potions
To start off go to arcons shrine in the nothern wastes and kill the wraths (froven undead) intill you have a combat multipler off higher then 100 u can do this by going back to the shrine or down the little path were u fish out the potion then go back and thay spawn again.
Ok now use summon when will goes low just use will potion kepp repeating intill the combat mulipler is quite low then just get it up again and repeat.
This is how i mastered all my will spells and everything .
Also if u whant to master ur guile and speed and all that use the money trick and you will get loads of exp for that two.
Hope this came in helpfull
