here's the most powerful build
1. scarlet
2.crossbow
3.pyromage
4.splinter
5.powershot
6.double shot
7.fan
8.shots behind you(can't remember the name)
9.(can't remember name) the upgrade to double shot which makes you shot like a shot gun
10.the tome that gives you an extra 100 ammo
result: a machine gun that also spews fire and has nearly limitless ammo