Celeste would write to Yennefer agreeing to supply some of the sap. She adds that a fellow Summoned reached out to her colleague, Osanna, for a similar request and notes that Ikorr is willing to work with both of them to do this.

Ikorr still holds its secrets, so they would not quite agree to teach her everything. However, they would tell her that - as Nocwich has offered to all those part of the Home Team who are seeking a cure for the ritual - she can enter the Nightbloom to retrieve some of their sacred flower, as well as go to Lunar Pond for the werewolves' moon-blessed water. They suggest she can attempt to experiment with all three ingredients. As a result of their contentious relationship with the Lunae, such a thing has never been tried before. They trust that, should she be successful, she will not make more of this substance without permission from both Luna and Ikorr, due to sensitive diplomatic relations.

If you'd like Yennefer to experiment further, you can have her interact with the Ritual Cure on the Event Coordinaton Post!