Board Thread:WARNING ALL USERS False Info\Spoilers/@comment-4148963-20140210024558/@comment-16072563-20140702183943

I think Deucalion did it out of addiction to the power. As a normal alpha, he was very much like Scott. Very idealistic about living in peace. Then Gerard  robs him of his vision, one of his betas tried to kill him and by doing so, Decualion became even more powerful. Now, he was addicted. He needed more power to compensate for his blindness so he kills off the rest of his pack and becomes the demon-wolf. Once he got his vision back, in which he clearly gives Derek credit for by sending Braeden to rescue him,  he seemed like a better wolf again. Deucalion is building a new pack somewhere.

In theory, if Derek can lose his alpha status by using his powers to heal his sister, I hink there is a way for Deucalion return back to being a normal alpha. If he heals enough wolves they can take a lot of that power away returning him to a normal Alpha.