User blog comment:B214/Question and Answers 6/@comment-185.112.105.215-20170106035554/@comment-10330822-20170106055457

I don't know if I'd consider Issei's Illegal Move Trinia as an irregular balance breaker. It's more of a fusion between the two are a result of a power-up.

It was explained that Sacred Gears are special in that they are a tendancy to combine powers together. Issei's balance breaker is still a regular, it just has another power as a result of a his ability to promote illegally.

Also, I'm pretty sure Kiba's irregular balance breaker is stronger.

Also, Saji's balance breaker is also an irregular, just pointing that out.