How do you get high crit in troll spellsmith class?

If your rank 5 you can use sigil attack.If you use sigil your damage get stronger if you stack it alot your damage gets higher max stack is 5 but you will losse your manna before you get to 5 so you should sigil then rest then sigil then rest if you wanna do a crit or just use a mana potion everytime you do a crit your manna gets realy higher.If you want high crit use all wizards enhancement but i use all luck because all wizrdas makes you unlucky but higher damage.You can do up to 3,500+ damage using troll if lv 50+