This is an expansion to the original Titan from Gorgonstar published in 1980.
Adds over 100 new monster counters to the game. Ten new character types. Eleven Expanded Tactical Displays.
Differences between the original, the expansion, and the Avalon Hill version can be found here: http://wolff.to/titan/oldtitanrules.html
The Avalon Hill edition compiled these two together in a refined release by AH in 1982.
Expands: