paradox42 said:
EDIT: Then again- it occurs to me that the Beetle is CR 50 in the same way that the Tarrasque is CR 20. A properly prepared group can smash it without thinking twice, and 50th level shouldn't be necessary. Feel free to run playtest combats against one yourselves, and see if you don't agree- consider all the spells mages have now that avoid SR, and factor in the fact that a fighter is involved who can use Giant Size 3/day and is a Greatsword specialist to boot. I'll bet the beetles won't last very long for anybody else, either. They may not be a "real" CR 50.
I think it's more accurate to say that the beetle is CR 50 in the way the 3.0 tarrasque was CR 20.
In other words... it isn't. Prepared or otherwise. It's maybe half its listed CR.
I just can't imagine any of the devastation vermin posing a significant challenge to an epic-level party, even low-epic. Not unless the party was comprised entirely of fighter-types who spent their entire level-appropriate wealth on +'s to armor and weapons, anyway.
Mind you, a beetle, for example, would take forever to kill, but it's very doable and, since the PCs should all be able to fly faster than the beetle can move, and to damage it from outside its reach, it's just not a credible threat. Actually, looking at the poor beetle, it's painfully easy to kill if you're not pressed for time: for all its amazingly high armor class, unexplained spell resistance and over the top AC, it
has no energy resistance. Anyone with a
fly spell, a bag of holding full of alchemists fire, and a whole lot of patience can kill it. (For reference, it would take an average of 784 alechemists fires to do the job, which would cost 15,680 gp

, so there's probably a cheaper/more efficient way to do it).