You need the stuff from the museum and you have to modify the weapon a little bit. The herbs and a tool from the doctors office are part of the solution. If I remember right, I placed hints in a book :-)
Got the green herbs small with the morser.. i just don't get it. Something is missing so i don't get through the fence. What to modify a weapon? Put all in the water in the church.. no difference. HELP.
Spoiler warning: Use the crushed herbs with the pouch, and use the result with the tomahawk. You need the magic tomahawk and the amulet. You do not need to take the books with you into the next chapter :-)
I have tried that before and again this morning: combining the pouch of ash with crushed herbs does not work. You might need to do something inbetween but i have no idea what...
