http://lord.nuklear.org/ - For a more hardcore game with strict rules

http://lord.stabs.org/ - More casual and less strict on its rules

Legend of the Red Dragon (LORD) was an amazing BBS door game made by some teenager (Seth Robinson) back in the late 80s/early 90s. It was really popular. I was 8 or 9 when I first played it and I wasn't very good. I never actually beat the dragon I think until I played it on Nuklear in 2004 or 2005!

The game is pretty simple, but it's also the predecessor to MMOs. In these Stabs/Nuklear games you are playing with 50-100 other people (not all at the same time) to kill the Red Dragon 5 times (or whatever number of times the sysop has set the game to reset at).