Unexplored known edges (not counting undiscovered secret doors, but including obstacles we haven't been able to pass yet):

• the river upstream
• the river downstream
• beyond the death propeller
• main shaft/hall down to level 3
• beyond the "three heads" door
• continuing down past level 4 (the throne room is on level 4)

Not sure if these count or not:

• Gravity Tomb
• Devil Face Floor

Samu adds:

Note to self
Unexplored known edges

• The Throneroom´s two secret doors and main door
• The 4 gargoyl statue doors
• Look for sercrets at the fountain of magic

If the warning are in order then the keys turn on the inside is inside the propeller room

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