User blog comment:B214/Volume 23 discussion blog/@comment-31137559-20170415054322/@comment-10330822-20170416031733

I feel saying they are overpowered is only relative to who they are fighting. Rias is not that overpowered in terms of people like Issei, Grayfia, Crom, and Vasco. In fact, she's probably Ultimate-Class at best, and that's pretty weak in this tournament.

Rias is very strong, relatively, and so is Gasper and the rest of their peerage, but Vasco and Crom Cruach are two of the only characters to hold a consistent edge over Issei. I'm pretty sure they edge out Gasper. The problem is Gasper's abilities are kind of vague, so he maybe more dangerous than he seems.