
While the primary ability of the Trees is to allow characters of the same sex (and even different species) to conceive and raise children of their own - the details and mechanics of this which can be found here in the Guidebook - the Trees have also gained two more special functions with the conclusion of the Board Wide Plot.
Once per lifetime, a character may travel to one of the two Trees of Life and make an offering to return changed - receiving either a partial or complete design overhaul.
Once per lifetime, a character may travel to one of the two World Trees and make an offering to either shorten or extend their lifespan by one year.