Dangerous Dave tileset format
Dangerous Dave was a game by John Romero published by Softdisk around 1990, first for the Apple IIgs and later the PC (under DOS). It was one of Romero's earlier published works, preceding the founding of id Software. It was succeeded by a number of sequels in the Dangerous Dave series.
The game tiles for the PC version were done in CGA, EGA, and VGA versions for the different graphic adapters in use at the time, with the CGA and VGA versions embedded in the executable and the EGA version in a separate file.