With all the great new monsters in IA it is a shame that the Ultimate bad guys have become pretty wimpy by comparison. After striving mightily to prevail against Ghost Spiders, Skeleton Lords and the new Golems the mighty Pit Fiend made an appearance in Spellhold. This Ultimate horror of Hell's 9th plane with his fear exuding multi melee psychic magic attack was dispatched in one round by somewhat prepared fighters. In the Planar Sphere the Demon's minions inspire more fear than they do as is the case even against the Demon Lords of Watchers Keep and even (gasp) Orcus.
Demogorgon is relegated to a footnote in Watchers Keep (the fortress built to house him!) surrounded by ultra and over powerful monsters. I personally think that he is not imprisoned at all but like an elderly citizen in his rent controlled apartment he has watched his neighbourhood go bad over the years and is now too petrified to step outside his front door! He has the gang banging orcs who just kill all day and the big dragon who wants to take over their turf right next door. And just upstairs he has the crack dealing illithids battling the meth dealing githyankis.We are talking about Demogorgon here !!! The Prince of Demons.
I realise that he is just an avatar of the real beast and therefore holds only a fraction of his power but that fraction should be plenty good enough to deal death and damnation to any adventuring party that plans on opening the great seal. Lets beef him up a bit so that attacking him is a real trial and thus get back to the situation that sealing him in becomes a reasonable option.
I think that the Balor in Underdark was an excellent fight but I did not notice that subsequent Balors were up to that level. Marilith's are tough adversaries but gain from numbers (alone these type 5's are meat) and the other Demons (for simplicity assume everything applies to devils too) are pretty generic and stupid foes. I think that more diversity in abilities and immunities would help as well as different tactics as opposed to having skeleton lord and grandlords do the heavy lifting. These guys should be the Grandlords! Demon's also dont gate in Skeletons they gate in ... more Demons. I think that there should be weak demons also , not all are powerhouses and I agree that not all Balor's , Marilith's , Glabrezu , Pit Fiends are created equal. However there are only weak Balors or Pit Fiends relative to each other they are the ruling elite of the lower planes and surely on the same level as Noble Rakshasas or Elemental Golems. Mariliths should be weaker than these but stronger than Glabrezus or Cornugons.
As a sidenote I believe that improving the power of Holy Word and Unholy Word spells is an idea worth pursuing.
I love the idea that forging Judgement day and gaining Daystar and Kitthix attract unwanted attention but perhaps forging The Truth should too as it is a weapon specifically designed to kill Demons. Perhaps something along the lines of "is it safe to rest?" whereby not so random monsters have a chance of a periodic visit.
.