I wish there were a clear reading of whether natural attacks count as IUS or not, since that's come up a few times with CC conversions.The MM gives Imp. Grapple to a number of creatures with natural attacks instead of Imp. Unarmed Strike. The hamatula is another example.
Sounds good.Urk, slow servers ate my post! Let's replace Iron Will with Epic Will. Also, if Epic Toughness is really going to be a bonus feat, we have one more feat coming -- Superior Initiative? Adamantine is a fine choice for Penetrate DR, sure. I feel like there should be some better choice than Cleave, and I'm a little wary of Improved Grapple for the reasons given above. Ability Focus (poison) or Ability Focus (hellfire) would make a lot of sense to substitute one (or both) of those.