Since she attacks a large area, and she has to be attacked in certain spots, it can be difficult.
But if you heal the ones that are in her attacking are you should make it.
Can take some time though.
Largonia (and Maggotheart), you are supposed to go trough all the rooms, in the last room there is a big "button", change all the small "buttons" to the same color as the big one. Ta da, the door opens.
My problem while doing this was that I couldn't see a part of the path in one of the rooms; it was all covered in darkness. Don't know if it is supposed to be like that or if it's a bug.
I hope my answer is comprehensible, and will help you =)
Best regards/ LNDN
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