User blog comment:B214/Question and Answers 6/@comment-26293136-20161102112256/@comment-9595671-20161102125549

Yeah, and Ophis can empower them to help them reach their balance breaker, but Azazel says trying to tap power form a sacred gear and not obtaining it naturally is dangerous.

In the cause of Ophis' power up? There's a risk the Sacred Gear can break, and if it breaks... the user dies.

I also think there's a chance of losing the balance breaker's access under this method. One member of the Hero Faction, the one who used the Dreamlike Curse gear, lost the ability to use their balance breaker after losing.