Is there any way to exchange the purchased branch for the real thing?I saved the game before the summoning but after Corrinna took items.Went and got branch from Talking Tree but can't seem to swap.Is it real important?
No, you can't swap if Corinna decided to put the wrong branch into the circle. It is not really important, she would have taught you "Banish" and you would have had another trader (for charms and spell books occasionally).
