Board Thread:Versus Battles/@comment-29853277-20171008102503/@comment-29853277-20171020212859

Probably not right away. But if he sees that Nico just won't die for some reason, he'd use his Sight to see why, and immediately see the connection.

That being said, he can prevent severed connections from reconnecting if he wants, so he might be able to just stop Nico regenerating if he cuts off his head.