Board Thread:False Info and Speculative Discussion/@comment-65.93.139.213-20150614214656/@comment-13965604-20150622153229

He didn't kill him because Scott had Jennifer heal the damage inflicted by Gerard. There is some meta over on tumblr speculating that Deucalion almost certainly had frontal lobe damage, which almost always causes severe personality changes like what we saw with Deucalion. When Jennifer healed him, she healed more than his eyes, she healed his brain as well.