I sold my first game in 1984; The game is called Zigurat (Ziggurat without a 'g'), it ran on Commodore VIC 20 and need to 2K RAM. Game was released on MC-Microcomputer, the best Italian Computer Science Magazine from 1981 to 2001. You can see the game and souce code at MC-Online site (Pages 147-148). My gain for this game was 60,000 lire (approximately 25 euro). Zigurat is a bidimensional game.
In 1994 I wrote and sold Zigurat 2. You can see a snapshot of the game on the left cover (the the ziggurat itself is the near the "E" letter of the word "XMode", a VGA extende graphic mode). The game ran on PC-DOS with VGA, and it used the notorious Xmode. Game was published on italian magazine Computer Programming (Disk). Magazine still exists, you may visit at this site. In the next magazine number I published a morpher, but that's another story... Obviously, I lost the relative source code. Zigurat 2 is a Isometric game.
1984 - 1994 - 2004. In 2004 I started writing Zigurat 3 (3D) but I have not yet finished. Do not believe me? On the left you can see the maze generator of Zigurat 3, and the strategic map generator. The game uses OpenGL or DirectX. But The Zigurat 3 project dies!
In late October 2016, Ziggurat4 alpha-0 was born! It re-gains a "g" and become an Android Puzzle Game Project. At the endt of October, Ziggurat4 v1.0 is published on Google Play and it soon reaches more than 11 downloads.
Try yourself Ziggurat4 alpha0 demo or Ziggurat4 demo.