User blog comment:Ḡwẵine Ḹٍٍkƨ Ĺiĸe Ͼềлȑềd/Where is everyone getting this Crystal Cave speculation from?/@comment-4062486-20121216072020/@comment-4190137-20121216072537

Okay I first of all think that it's a bit of a hold-back if Merlin's magic is contained in the finale, because I mean... the episode is supposed to be as epic as it can be! And Merlin losing his magic is (especially since it's the finale) also a bit of a cliché.

Anyway, the Taliesin wasn't credited in the press release. So I think it's extremely unlikely he will appear even if Merlin does go to the Crystal Cave.