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syntax: commune 'forest haven'

Forest Haven allows a druid to call upon the wilderness for
asylum, allowing them to quickly transport themselves elsewhere
in the forest
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What are the requirements for this to work? Are there any restrictions? I've seen druids forest haven out of entwine in the Imperial Lands. Doesn't seem that a forest is even required. Any help appreciated.

I'm guessing that would be this edge:

FARHAVEN
Druids with this edge may be able to use their Forest Haven prayer even in a non-
wilderness area, if the moon isn't full.

See also: Help EDGES

and there is plenty of that.

If the terrain of the room allows it and you can magically transport you can forest haven. Functionally it is the same as vanish. Not sure if entwine/fighting/terrain type affects your chance but it was pretty reliable the few times I had it.