There is only one file type that uses the .TTL extension:
AGT Game Title File
File used by Adventure Game Toolkit (AGT) interpreters; contains game title data referenced by AGT games; includes the author's name, name of the game, and copyright statement that are displayed before the game begins.
An AGT game consists of typing commands to navigate through a story, similar to a choose-your-own-adventure book.
AGT games can be packaged with a wide variety of files that contain game data, including DA1, .INS, and .VOC files. Because of the large number of files that accompany the AGT game, the files can be converted into a single .AGX file with the AGT2AGX utility that comes with AGiliTy. This conversion reduces clutter, decreases load time, and reduces game size over 100K.
[name of the game].ttl - The TTL file will be named after the game.
Updated: June 28, 2014