Is this in arena or in the Campain. In the Campain Mortu-Macaab has Allmighty immunity which blocks the block passive skills debuff

It happened on Doom Tower Hard Floor 94.

So, I believe this has to do with the fact that Peril is a hidden skill and neither a passive or active. Once unlocked it cannot be prevented 

Thanks for your answer, but my opinion is that the "hidden" reason is not acceptable, because it is a Passive skill. (you can see the "P" character on the skill icon too)

i

I would like to ask a solution.

Was Mortu hit before Ronda placed this?

Yes, and probably this is the explanation. Thanks!

I will keep testing. 

👍

If you run into any other issues, feel free to pop back in.