This is a collection of bits and pieces that have, over the years, come together as a set of House Rules for my long-running (twenty years and thirty-odd players) Pangea campaign, set in a home-brewed world that happily poaches elements from all manner of RPG and Fantasy sources. Given the Frankensteinian nature of the AD&D 2nd Edition system, it's always been easy to fiddle with whatever rules suit you, unlike, (for example), the 4th, where the system is pretty much self-contained.
This might seem a little strange, what with the all-conquering releases of the later editions, but I can't face the effort of trying to convert my bumpf to the newer rules, and in any case I still prefer many of the interpretations that follow (he wrote, modestly). If Pathfinder or 3.5 is your bag, the alternative systems I detail on this site can often be mixed in anyway...
My endless thanks to all those who have helped, inspired and otherwise come up with the systems that follow. If I have forgotten to credit you for something you specifically devised, I apologise - email me and I'll amend whatever needs changing asap.
As regards what follows: anyone is free to use, download and muck about with these ideas, unless they're planning on making money from or otherwise publishing them elsewhere. In those cases, use is expressly forbidden unless I give written approval - email me, and we'll see what we can do. Furthermore, these ideas are in no way intended as a challenge to the rights or trademarks of TSR, WOTC or any other interested parties as regards their property.
AD&D is a trademark of WOTC Ltd.
Here's the most radical change I'm using in my games. Succinctly, it's to substitute 2d10 wherever a 1d20 is called for in the rules. The idea behind the change is to make AD&D less 'swingy'; less random and unpredictable. Results towards the extreme ends of the scale are much less frequent. This has a number of ramifications which, to be honest, we're still discovering. For example, low-level combats involving creatures with high ACs are more dangerous - folks in platemail are noticeably harder to hit. Also, the effects of a bonus or penalty are more pronounced; a +3 is a big bonus on 2d10. I've assumed that 2d10 rolls are in effect on many of the tables in these rules; it should be no problem to change them back if you want to stick with 1d20.