Madness and the Minotaur is a text adventure game for the TRS-80 Color Computer. Developed by Spectral Associates in 1981, the game lulls players into a false sense of security by providing a comparatively easy and static early game. Once the player walks down the stairs, however, the game rapidly degenerates into what may be the most difficult text adventure labyrinth ever created.
The goal of the game is to retrieve a number of treasures. In the course of doing this, the player will encounter other objects that may or may not be useful. Often, the player needs one object to act as a "key" for another. There is no rhyme or reason to this. The player doesn't use the key object to obtain the other; he just needs to be carrying it. For example, the player may see a shield. Perhaps the player needs to be carrying the dagger to get the shield. If the player has the dagger, the shield is reachable; if he does not, it is not.
With the exception of a randomly appearing "oracle", the game gives no indication of what objects are needed to reach a treasure. There are various magic spells that can be learned throughout the game that have various effects.
Source: Wikipedia, "Madness and the Minotaur", available under the CC-BY-SA License.