Of course there's always the Web Enhancement. You can chuck epic-level CR 40+ stats for the demon princes on such a thing since it's for a minority of people that want it. At least I believe there is. I haven't seen a new epic feat or epic monster like that awesome Gravwyrm on the WotC Website Monster Mayhem (or was it epic insights?) since.....wait, what is epic material again?
Personally think it's easier to downgrade a powerful fiend than to upgrade. If CR 50 isn't what you need, lower Hit Dice, damage and SR, not the other way around.
Personally think it's easier to downgrade a powerful fiend than to upgrade. If CR 50 isn't what you need, lower Hit Dice, damage and SR, not the other way around.