No other trait in the game has any classifications. I suspect that this comes from Demonic Revenge's past life as Demonic Pain. This matters because it is currently cancelled by Defensiveness.
Actually, it seems to work correctly here... Demonic Pain and Demonic Revenge have been separate cards before. It's just weird.
It is also discarded by counterspell and forgetfulness if your opponent manages to cast either before you had time to play your traits.