Probably no surprise on my end: AD&D 2nd Edition, Revised and Expanded, with all Player's and DM's Option books, tweaked with a number of house rules.
A friend introduced me to AD&D with the Mystara campaign setting and I started being a DM with the second Forgotten Realms campaign setting box. We've been playing since the mid-90s. What I like most about late 2e, is the vastness of compatible rulebooks and lore. I can use books from 1e through 2e P.O. That's more than twenty years of releases, 1977 to 1999. 1e converts with minor tweaks, so you can do it on the fly. However, I'm afraid that when I die and want to turn away from the light, Gary Gygax's Amnizu lawyer will show up and say "Not so fast, buddy. Didn't the rules clearly say 'no magic shops?' Guards, arrest him!" Yes, all the bad rep for tedious maths, cryptic tables and endless browsing in multiple books is justified. But, we probably modified every rule that didn't fit our style of play, and the ongoing campaign of course also changed the worlds we play in. These days, the group is still based in Waterdeep, but we're also using Planescape, Greyhawk, Spelljammer, Mystara and Ravenloft resources in almost every campaign.
When 3e came out, we had all hoped for a modernisation of the existing rules, not a complete cut. We actually adapted 3e Saving Throws in happy anticipation when they were introduced in a magazine ahead of the release. We simply didn't expect WotC to break the rules, the continuity and the style of playing like that. When I was done reading through the new books, at first I thought I was missing something. TSR was often antagonised, and rightly so, for spreading rules across three books you had to buy. But this was different. After trying to convert, or rather "re-imagine" three important NPCs, I realised that we would not be able to continue our campaign with the new rules. No working combat system, most spells were transmutations all of a sudden, and FR had lots of pretty silly retcons that couldn't be explained - not to mention what they did to the cosmology. The wizard and fighter could maybe have switched to playing rhythm guitar and triangle in the henchmen band away from danger, but the Ranger was just completely broken. We would have lost compatibility with my existing collection of rulebooks and all the campaigns based on them. WotC also broke the continuity with the race of one PC not even available in early 3e. We therefore voted against a new start and I've been developing the world myself since then. With almost every TSR release available as PDF and several Fandom pages, all the browsing and planning has actually become fun instead of the drag it used to be. No regrets!
