ZZT

ZZT is a action/puzzler created by Epic Games. Running entirely in text mode, it is basically their answer to Apogee's Kingdom Of Kroz series. It consists of three games (or rather, three scenarios for the same game), as well as the sequel Super ZZT, which is essentially the same but in a scrolling lower-resolution screen with a few extra objects. A ZZT fan named Gregory Janson later released Mega Zeux, a Spiritual Sequel to ZZT that massively improves on the extensibility of ZZT's engine.

It is best known for its editor, allowing users to create their own games. It uses a simple programming language that can be used to make objects do whatever you want. This is one of the earliest games with a modding community, and literally thousands of such games can be found on the 'net.

ZZT was very popular in its heyday and there is still a sizable ZZT community, though they rarely make games or even talk about ZZT... Back in the day, the community cranked out great games such as Teen Priest, Burger Joint and Evil Sorcerer's Party.

ZZT became Freeware Games several years ago. However, because the source code no longer exists, the copyright and ordering information can't be removed from inside the game.

General tropes associated with the engine:

 * ASCII Art
 * Blackout Basement: Some screens are dark, requiring the use of a torch to have limited sight.
 * Dialogue Tree: An option for characters.
 * Excuse Plot: most of the scenarios
 * Fun with Acronyms: Though ZZT didn't originally stand for anything, it has been joked that it means "Zoo of Zero Tolerance".
 * Interchangeable Antimatter Keys: Mostly - keys come in 7 colors, but if you already have one key, another key of the same color cannot be collected and will instead block your path. Many puzzles are deliberately centered around this behavior.
 * Level Editor: Most people agree that this is the best part of the game (much to the surprise of the game's creator).
 * Locked Door: The original episodes revolve around getting purple keys to reach the final area.
 * Nintendo Hard: The game tells you from the start that you'll need to save a lot.
 * Power-Up Motif: Collecting an energizer (which provides temporary invincibility) causes the player to flash and also plays a jaunty tune. When the tune finishes, the energizer effect also stops.
 * Respawn Point: Some rooms are set up so the player warps to where they entered whenever they are hurt.
 * Space-Filling Path: This is a problem in some games.
 * Ten-Second Flashlight: Torches
 * Unwinnable: it's possible to end up in e.g. a position where you need ammunition, but with none left.
 * Xtreme Kool Letterz: The name ZZT was chosen so that it would appear on the bottom of Usenet listings.