he will lose his body and soul and most likely turn into the Beast.
His soul is bound to go to the Vortex of Souls once he dies. As for the Beast, it's a manifestation of his mental state - not something he can become. (Plus he couldn't become anything if his body was eventually consumed by the armour.) But, hey, if he were to become an apostle (which would be a game over), chances are he'd look like the Beast.
Akshully, they're episodes. In Berserk, it goes arc-chapter-episode.
Also, confession time: I dislike the berserker armour.