Faellys is normally forbidden terrain for non-fae - or 'diflas' - but the party managed to convince the guardian of the border,
Thymerion, that their cause was just. He has decided to test their intentions and willpower via a strange trial, basically taking place in the mind of Thymerion himself. The party is presented with a number of challenges around the themes: expectation, desire and fear.
After the trial, Thymerion deems them worthy of his trust and sends them on their way to the moontree, giving them protection in the form of an enchantment to make them seem like fae-creatures to divination magic and the forest itself and a couple of potions to make them able to speak the faen language.