I don't honestly see this coming up. Over the normal course of play, after months and months, maybe even years, I can't see someone saying, "Hahaha! Now I can do infinite damage to Orcus and kill him!"
Besides, the reality is that, if you're going up against Orcus, he knows you're coming, and he's probably not going to be identical to what's in the book. There will be bad guys to get to him and all of this other stuff that will make it so that people may have already used most of the stuff.
It's always easy to say, "Well. If I'm standing here and do this and he's standing right in front of me with his thumb up his ass, I can maybe almost do enough damage to kill him if I roll 15 attacks and don't mess up."
Right. Have fun with that. The reality is that you won't be at full everything, might not win initiative, and he might be able to one shot you. Good job with all of that.
Is it powerful? Yes. Will it ever really happen like people are hypothesizing? I seriously doubt it.