In 2003 I made a little 1024 byte Commodore 64 game called "Marz" for the Minigame Competition, which was an annual online 8-bit programming competition. I've found the 6510 source code to it - let's take a look through it in the Turbo Macro Pro assembler. To support 8-Bit Show And Tell: Become a patron: https://patreon.com/8BitShowAndTell One-time donation: https://paypal.me/8BitShowAndTell Credits music by: https://bedfordlevelexperiment.bandcamp.com/ Links: XIP (minicompressor by Steve Judd): http://www.ffd2.com/fridge/rad/ Marz disk image: http://8bitshowandtell.com/downloads/marz.d64 Disk instructions: LOAD"MARZ",8,1 to just play the game - it automatically starts due to tricks in the xip decompressor Use a REU on your real C64 or emulator to follow along: To build with Turbo Macro Pro+REU: LOAD"TMP",8,1 SYS 32768 {back arrow} L, filename: MM29 {back arrow} Shift+R, L, filename: UFOSPRITES, location: $3F80 {back arrow} Shift+R, L, filename: LASERBEAM2, location: $3FC0 {back arrow} 3, S Hit the RESTORE key to re-enter TMP TMP Documentation here: http://turbo.style64.org/docs/table-of-contents New index (from 2020.12.01 edit): 0:00 Intro - Marz source code 1:39 The Minigame Competition - my entries 2:32 Loading the source; xip compressor 3:59 Diversion: Terry Cavanagh and bad source 6:26 Loading the sprites 8:16 Playing the game 11:00 The iOS version I made once 11:32 Walking through the code: memory layout, the labels 13:55 Game initialization - once per boot 15:45 Play initialization - once per game play 19:12 Level initialization - once per level 26:21 Game loop - once per frame 27:35 Ship to building collision - game over 29:29 Bomb to building collision 36:05 Moving the ship - wrap around and descent 38:30 Ship sprite animation 40:40 Fire button, dropping bomb 43:00 Checking for end of level & end of game loop 46:34 Building the level 51:00 Some misc subroutines - raster & sound fx 53:00 Update sprite positions 54:05 Other misc subroutines 54:45 Thanks to my patrons!