You know, I just read that whole Bloodstone series last month giving it serious thought to conversion. I almost popped a question to the boards myself to see if anyone had started the project for colaboration. Unfortunately, I also lost a significant database when one of my hard drives crashed earlier this month and I put all thoughts of conversions out of my head until I could recover that information. Anywho--
Nightmare keep was an odd adventure, if my memory serves me. It was a high level and did not have anything leading up to it. I also think it was an early second edition adventure instead of a first ed. Not much of a difference there though. Unfortunately, direct conversion from first or second edition into third can produce some very unbalanced encounters or even adventures. What I have had to do (and I am not able to publish these conversions on the net because of the
OGL) was to take each encounter as a unique entity and modify the opposition to fit more into a standard progression for the module at that point. For example, I converted an encounter with three water wierds with the first version of them from 3 ed MM2 (at least I think it was, it has been years since I did this) and discovered that they went from a minor nuisance as they should have been in the original edition to an equal to the main badguy at the end. To make it worse, once you finished them off or bypassed them, you had a 75% chance of encountering a mature adult black dragon in the next five minutes. I had to modify that encounter on the fly after about two rounds into it when I started mopping the floor with the PCs on a direct conversion. Basically, I cut the power of the weirds in half and dumb played them a bit. Fortunately, since then, another version of the water weird has been published that more closely resembles the nuisance weirds from that module and I can use that version as is. If you have access to Libris Mortis, I would use that to spice up those undead encounters, especially the ones at the end, and that can increase any encounter levels you may need. This also means you won't get to share it with us on the boards though, since Libris Mortis is not an
OGL source book.
For the Throne of Bloodstone, I am sure that one is a second edition. It was the only one of the series that was. In any case, that makes little difference in the overall scheme for conversion. Thoughts of encounter levels make my head hurt, especially since almost all random encounters are with demons of various types. In this adventure, I would make a pinnacle of a campaign. Whenever the PCs are getting that been there and killed that attitude, it is time to bring this one out and see if they can beat Orcus at his own game. A couple of points for your questions though: Orcus has an extensive overview in the Rappan Athuk (final book if you get the series instaed of reloaded). He even has three different versions based on some of the earlier encounter results that affect his "being". This would just be a source for you since in the ToB he is attacked in his home plane and not on the prime material. Also, using it would again prevent you from sharing with the rest of us. But I would highly recommend using everything you got in this conversion and not restricing yourself to just the
SRD. Like I said, it should be a pinnacle...with Zenghyi, I suggest using Libris Mortis again. Bump him up to what you need to start this whole thing off. He is the leader of an entire nation afterall. I would also suggest using the Draconimicon and Races of the Dragon for an additional feat pool for the dragons in the adventure and to help flesh out Tiamat. She is the deity of the dragons at the time of this module. There may also be some info about her avatar in RoD or Draconimicon. This can be used as a starting point for her abilities and you can beef her up from there to any level you need to face the party in that final confrontation.....I just reread you info from the post and I see there is an entry on her in Manual of the planes. Just remember that that book was one of the final from the third edition before they revamped everything to 3.5, so it is not unreasonable to expect her to change as you need her to.
Here is another thought....are the PCs bringing anything else on this grand quest other than themselves and their pool of magic? Followers, hirelings, an army maybe? I know that in the way the CR system is designed, these things are supposed to be taken into account as part of the PCs actual power level, but in reality, they are just as significant an addition as a low level wizard that somehow summons a mid level demon to help him out in a fight. Things get quickly unbalanced. At high level, this is even more prevelant. This may not have been much in the way of help in the encounter level or starting level areas you are looking for, but these are the kinds of thoughts I have when I am thinking of converting these adventures.
, I believe an 18th level wizard, which would make him a CR 20, and he also had some pretty deadly encounters in his tower, as well as a powerful white dragon... not too sure of the age category off the top of my head, but I think maybe Ancient, so CR 18... anyway, then there's the whole "stealing the wand of Orcus" 
(Orcus CR 28 per Libris Mortis and Book of Vile Darkness) and "getting Tiamat's heart" 
(Tiamat CR 25 per Dragon #272 and Manual of the Planes) deal... Anyway, my estimate (this one is a lot harder!) is maybe EL 18 for the first part of the adventure, and EL 23 for the second? Remember, you don't have to KILL Orcus, just get his wand... Tiamat though is a dual to the death, and she has her powerful consort chromatic dragons with her as well... Is that too light? Maybe EL 20 for the first part, and EL 25 for the second??
Linear Mode
And yet another word from our sponsors
