For those who don't already know, this document combines three things, in about equal measure:
First is a compilation of all of the AD&D material I know of written or explicitly approved by Gary Gygax that wasn't compiled into an official AD&D rulebook during his tenure at TSR - including new monsters that post-dated (or were left out of) the Monster Manual II, material from Dragon magazine that post-dated (or was left out of) Unearthed Arcana, assorted acknowledged-but-uncorrected errata for the rulebooks, and even an unofficial new AD&D class (the Hunter) that Gary published in New Infinities' short-lived "Realms of Adventure" newsletter in 1988.
Second is material that I adapted to AD&D from Gary's two post-TSR systems - Dangerous Journeys: Mythus (published by GDW in 1992) and Lejendary Adventure (published by Hekaforge Productions in 1999) - including joss, knacks and quirks, "spellsongs" for bards, new weapons, and several abilities for the jester and acrobat classes. There's a lot of interesting material in both of these games that showed that Gary was still actively creating and expanding his concept of fantasy role-playing in different (and, IMO, more interesting) directions than TSR was taking the official game, that when adapted to the AD&D paradigm can help bring new freshness and possibilities and remind us of the period in the 80s when AD&D was all about expansions and new material, and not the later eras when (due to lack of high-quality new material) it became increasingly hidebound and ossified.
Last are my own house rules and expansions compiled from several decades of play - including my preferred "fixes" to various problem-areas in the rules (like psionics, weapon specialization, and various under- or overpowered spells), my versions of some of Gary's proposed-but-never-detailed new AD&D classes (mystics and mountebanks), and various "cheat-sheet" documents I made for myself over the years covering topics like how to go about hiring mercenaries, what you can find at each type of shop in a typical town, all the rules for wilderness adventuring that are otherwise spread across tons of rulebooks and modules, a quick-reference for the relevant details on all of the World of Greyhawk deities, and so on.
This document is extremely unofficial. I don't have permission from the copyright owners for any of the reprinted or adapted material, and it doesn't comply with the terms of the Open Gaming License (because I wanted to directly refer to the AD&D rulebooks and World of Greyhawk and not have to speak in code or pretend I'm talking about some other game). That's why I've kept it low-key. My position is that this is an amateur fan-production, intended solely for the private and personal use of me and my friends, and the last thing I want is to receive a cease and desist letter from Wizards of the Coast of the Gygax Estate.
That said, despite this document's humble ambitions (and even more humble production values), for anybody who reads this blog and enjoys the same flavor of AD&D as I do - who doesn't think the game ended with the publication of the Dungeon Masters Guide in 1979 and everything that came out after that was a mistake - I think there's value in it. If nothing more, having the compiled articles from Dragon and the monsters and magic items from the late-era modules all in one place should be convenient. It doesn't cost anything to download the document and take a look!
Anyway, that long preamble out of the way, the reason I'm mentioning this now is because I've just uploaded a new "version 1.3" of the document - the third revision since I originally posted it last year. The changes between this version and the previous one are the notes on barbarians and cavaliers that I've already posted here, and some additional compiled material - a bunch of changes and additions to the creatures in the Monster Manual from TSR's Monster Cards that I'd previously overlooked, a previously-overlooked note on halfling stats from Dragon #95, and a few more monsters and magic items from modules that I hadn't previously included. I'd like to think this is the "final, final" version of this document (I say that every time I upload a new version), but I don't actually believe that to be true anymore. As proof, already since uploading this version I've realized there are several typos that a reader pointed out that I forgot to correct...
The link over on the side now goes to the updated version (EDIT: now with corrected typos!). Or you can click here: https://drive.google.com/file/d/0B4BiigPc-r3FNFlRUGliemhqRmM/view
I hope if you haven't seen it before that you get some useful material or inspiration out of it. And please don't do anything with it that will get me in trouble with Wizards of the Coast or the Gygax Estate!
EDIT (12/8/17): New version uploaded: https://drive.google.com/file/d/1OrQfLGV4DdJmox2VrVzOLiczBj4XutKo/view
I added one small but significant paragraph on page 7, regarding barbarians:
Barbarians able to harm creatures only normally affected by magic weapons (as described in UA) gain an actual bonus to hit and damage on melee attacks (i.e. +1 at 4th level, +2 at 6th, etc.). Furthermore, any melee hit by a barbarian that totals 21 or better after adjustments scores double damage. Both of these advantages are, of course, lost should the barbarian ever deign to wield an actual magical weapon.Both of these additions come from Gary's write-up of Conan in The Dragon #36 (which obviously formed the conceptual baseline for the barbarian class), but were dropped from the class write-up itself in Dragon #63. Presumably that was done because they were felt to be too powerful, but doing so ironically made the class too weak at higher levels (as noted by Gary in Dragon #67) which UA "solved" by gradually lifting their restriction on magic item use, which is lame (since it undermines one of the core conceptual hooks of the class and contradicts Gary's claim (also in Dragon 67) that barbarians don't change and become more sophisticated as they increase in level, they just get tougher). By reverting to the original Conan write-up and extending these two abilities to all barbarians, balance is restored - high-level barbarians remain comparable in combat ability to other fighter-types without having to debase themselves by relying on witchcraft and magic like a coward or weakling ;)
EDIT (1/1/18): Another new link to the latest new revision (version 1.4) - https://drive.google.com/file/d/1-B5CgUVByZBMM7Pn-tEJ1FzYZl3HxU2F/ Various changes from the last version are on pp. 32 and 73-77