Board Thread:False Info and Speculative Discussion/@comment-544940-20160309130458/@comment-26879545-20160328173756

NishHound wrote: The side effect of him being the beast is that he would no longer be of existence!! thats the only side effect. Sebastien learned the  names of parish hayden and he also learned to drive a car through the memories of mason.

and yeah mason just happend to be a good guy with 2 sets of DNA. thats the beauty of the show. how scott will save his betas best friend. Scott saved stiles last time when he was possessed and stiles is a good guy.

but we dont know what would happen after mason was saved. but i dont think they will go in detail regarding that mason would be like "i have never felt better in my life" lol  i dont think there would be any side effects. its like for stiles. He was possessed by an evil spirit and now hez all better. I think its safe to say that stiles life was in danger than masons life was. Because the nogitsune was became Stiles and they split into half and when the nogtisune was becoming powerfull Stiles was dying. But for mason that wasnt the case. That's not a side effect, that's the end result of his possession. A side effect would be something like moments of supernatural senses or strength, or, similar to Stiles, Scott and Allison (before she died), a mark left on their soul due to their temporary death (assuming Mason "died" at all).

Speaking of temporary deaths, Stiles isn't all better. He still has that stain on his soul from being one of the surrogate deaths. He may have closed the door to his mind, but that "mark" is going to be there for the rest of his life. Deaton even said so. The show even mentioned it with Theo saying "The Nogitsune is gone, but Void Stiles isn't." He and Scott are always going to have that darkness in them until they die... unless the writers conveniently write in a way for the darkness to be wiped away.