Magocracy

From the author:

Magocracy is not like most Interactive Fiction games. It has a healthy dose of MUD-like combat, but hopefully you won't find it to be very MUD-like either. There are a few puzzles to solve around the castle, but the main obstacles are the other Mages in the game. These Mages should be thought of as players, just like you. Each one of them can move about the castle, pick up objects, find secrets, and get into fights. They also each have their own unique special abilities. These abilities can be yours if you are able to read their spellbooks. The goal of the game is to defeat the other mages and learn their secrets.
You'll find that you won't last long in direct combat with most of the Mages, you'll need to use your own special abilities to gain the upper hand. You can learn to use the spells you know by reading your spellbook. Your spellbook will also automatically record any new spells you learn.
There are many possible strategies that may lead to victory. You could try to find good weapons and armor, and improve your combat skills enough to defeat another mage in open combat. You could wait until two mages start to battle each other, and then snatch the items off of the corpse of the loser. You could even discover the secrets of the castle, and use them to your advantage. There is a lot of information about the game hidden in the game itself. Try reading books in the library or asking the other mages about various things. Try watching what the other mages do, and imitating them after you've taken their powers. You could even try to avoid the contest altogether, and see what happens when the other mages are left alone...

Magocracy was written by A. Joseph Rheaume using TADS 2 by Michael J. Roberts.