Stuck at pit of hell

So I just beat the dragon king and I thought I completed the game but I just found out I have to go to the pit of hell but I find it impossible. I can't even attack the undead servants, well I can't even walk forward I just stand in the same place and almost die everytime I get attacked, I just used 46 full health potions with out even attacking once. I beat this game before but it was almost 5 years ago so I forgot a lot about it, what do you recommend I do? Any help is appreciated 
