Game Details:

• Screenshots include title loading screen, level 10 gameplay snapshot, and combat round snapshot.
• Created in 1983, it's one of the first computer games.
• Gameplay involves navigating a small tank, shooting down few-pixels aliens like alien1.png, alien2.png, alien3.png, alien4.png, and stealing few-pixels uranium blocks.

Gameplay Features:

• 160 x 100 16-color mode (text mode with character height register changed).
• Bonus round: Shoot down a small UFO (displayed as alien4.png) in level 2 to play a simple shooting at alien character that moves faster with each hit for more score. After missing, the round closes.
• New lives: Reach score 20,000 to get an extra life.
• Hacks, tricks and cheats: Some UFOs have negative values. Hex editor can be used to set starting level, starting lives (1-7), and set certain bytes to 0x90h to prevent lives from decreasing.
• Found bug: Changing code to not decrease lives leads to more frequent blue unpredictable monsters and longer time for red collector to start collecting uranium blocks, making it hard to finish levels. Can't reach level 99.

Running in DOSBox:

• Download MOONBUGS.ZIP and unpack moongbus.com to DOSBox folder.
• Or download patched MOON98.ZIP without decreasing lives, starting at level 98 with one life.
• Create a new DOSBox config file, modify cycles to 300 (4.7MHz), machine to cga, and in autoexec section, add mount d c:\games\moonbugs and d:.
• Run DOSBox using the configuration and type moonbugs.com. Use F1 key to fire.

Other Info:

• The game has 50 KBs of code + data together.
• There is an example of filling the screen with 0xDE character.
• Initial level and lives values can be seen in disassembled code.
• Related web page: www.digger.org for Windmill Software and the game Digger.