I don't know if its me, but i don't think the free will shield or heal takes effect all the time. i see the heal, but there are times when i get one shotted with the shield on, as if it wasn't even there. any explanation?
so i managed to beat the boss at level 33... i started out with daggers and went straight for the extra souls. i maxed that out, got the nimble movement, (wasted about 3 levels on the other 3 skills in the tree) then i switched to a staff. i had everything but regeneration maxed, maxing out the penetration, then the tidal wave mastery, then misc afterwards.
to grind for money, theres a trick. only beat on the door a couple of times, (and if you do more then 25% of its health just take it down and move on to the next one) and kill the creep by running through them then immediately attacking their backs afterwards. never stop in a sandwich, just move back and forth and they'll all eventually die. this only seems possible after you get the nimble movement, and it gets easier once you buy the ring for extra movement.
so i broke the game... i accidently hit my sauce at the exact moment that something grabbed me, and so my burger became invisible and now the upgrades section says i have everything maxed. (meanwhile all the buttons are flasshing boots and lettuce, and i have 809,660 money)
 "Sonny 2"){kind=icon}
 "rocket 1.3"){kind=icon}
 "Chess Evolved Online"){kind=icon}
 "Supermechs"){kind=icon}
 "Medieval Cop - The Princess and The Grump"){kind=icon}
 "Zombie And Juliet"){kind=icon}
 "MadBurger 3"){kind=icon}
 "Rebuild 2"){kind=icon}
I missed a few. Sorry for the inconvenience. :(