Retrospective: Dungeons & Dragons Immortals Rules

In the early days of the OSR, a common topic of discussion was D&D's endgame. Both OD&D and AD&D assume that player characters, when they have achieved higher level, will settle down to rule baronies and become movers and shakers within the campaign world. There's little disputing this, since even a cursory reading of the rules reveals that this was clearly the intention of the game's creators. Unfortunately, neither game provided much in the way of explicit rules or even guidance on what this intended endgame would look like in practice, which no doubt contributed to its loss. 
It wasn't until the release of Frank Mentzer's Companion Rules boxed set in 1984 that D&D players were a clearly stated version of D&D's intended endgame, however inadequate one might judge it (I personally liked it, but I recognize that not everyone feels the same). However, for reasons I've never understood, the Dungeons & Dragons game line, starting with the beloved revisions of Moldvay, Cook, and Marsh, was obsessed with the number 36 as the highest possible level attainable by a character. That's why Mentzer followed the Companion Rules with the utterly pointless Master Rules : to fill in the level progression gap between 25 (the top level of Companion) and 36, the inexplicably Highest-We-Mean-It-This-Time level for D&D.
Given the vacuity of the Master Rules, one might be forgiven for thinking Mentzer had finished with his revision, having provided rules coverage all the way up to the lofty heights of Level 36. You'd be mistaken, of course, because Mentzer had one more trick up his sleeve and it was a doozy. 1986 saw the release of the fifth and final boxed set for Dungeons & Dragons, the Immortal Rules. As its title suggests, this set focused on characters who had achieved, in the words of its preface, that "most ambitious of goals – Immortality itself." Now that's an endgame.
I should immediately note that becoming an Immortal is not the same thing as becoming a god – or at least not exactly. The Immortal Rules appeared during the "angry mothers from heck" era of TSR, when the company was doing everything it could to avoid giving offense to Middle America. That meant eliminating or scaling back anything that skirted too close to religion or religious belief. Hence, Immortals, though they "oversee and control all the known multiverse," are explicitly not its creators. More importantly, Immortals do not seek – or receive – the veneration or worship of mortals. Instead, they have their own goals, which largely consist of exploring and understanding the mysteries of the multiverse and its infinite planes beyond the Prime.
The rules governing Immortals are clearly derivative of those in Dungeons & Dragons – there are, for example, still six ability scores, armor class, hit points, etc. – but most of them have been thoroughly re-imagined or re-contextualized – so much so that they're scarcely the same game anymore. Most importantly, a character accumulated experience points are converted into power points on a 10,000 to 1 basis and those power points are used by the player to purchase talents and abilities for his now-Immortal character. As an Immortal learns more about the multiverse, he acquires more power points, just as normal characters acquire XP. These new points can then be used to buy new abilities and to advance within the Immortal hierarchy. 
What Mentzer has done here is effectively turn D&D into a more freeform point-buy system that is wholly unlike the class-based structure of "ordinary" Dungeons & Dragons. I remember, when I first read the rules, shortly after they were published, just how odd it all seemed to me. Now, to be fair, I had absolutely no idea what the Immortals Rules should look like. For that matter, I wasn't even sure that there was much point to rules for player character immortality. All I can say is what I expected and that was something similar to the D&D rules of levels 1–36, though at a greater scale.
That's not say that what Mentzer does in the Immortal Rules isn't interesting, because I think it is. He clearly had a strong idea of what Immortals were within the cosmology he'd created for the game and, knowing that, the kinds of powers and abilities they should possess. Then, as now, the question is one of why? Did anyone really want these rules? Did anyone ever use them in play? I certainly never did. I read them a couple of times and then largely forgot about them – not because they were badly done but because they scratched an itch I'd never had. Re-reading them in preparation for this post, I can't help but think that the Immortals Rules existed only to fulfill some vague sense that D&D had to include rules for immortality eventually. 
I suspect my own interest in the Immortal Rules might have increased considerably had Mentzer done a better job of fleshing out just what Immortals did. He talks a lot about exploration of the multiverse and of learning its secrets, but, aside from a few small details here and there, he doesn't provide any practical examples – in a way, recapitulating the problem of D&D's original endgame. It's a shame, because I think there might have been room for a wild and woolly multiversal game at the pinnacle of D&D's level progression. That's certainly in keeping with some of the stuff with which Gygax had long been toying, so it's not in any way alien to Dungeons & Dragons. 
Mentzer's reach exceeded his grasp with the Immortal Rules, which is no crime – but it is a disappointment.