well, they could just make each epic mob a 'living portal' like the portals from the shroud. Immune to everything, takes forever to kill, no crits, and we just swing to take down the 20,000 hit point portal..
and it hits us a lot for 80 points damage..
pretty much close to the original epic in a way...
I think for many, that would cause online character suicide and dents in our heads from banging them on the wall though.