Gauntlet by Donald R. Lebeau, 1984
forums.atariage.comA forum thread about an obscure Atari 800 shareware game and the search for the registered version that was presumed lost. The developer appears and gives a lesson on 6502 game engine programming techniques - and the harsh realities of the shareware market in 1985.
This was known as gauntletak. Not the 4 person super hit of the same name. Wikipedia for this: https://en.wikipedia.org/wiki/Gauntletak