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In the style of games made the 8-bit generation of game consoles & computers, or sometimes authentically created to run on original hardware. Common 8-Bit consoles include the Nintendo Entertainment System, Sega Master System, and the Commodore 64

Pretty sure everything is indie on itch.io but just in case you want something extra indie.

Pixel Art refers to the charming, simplistic, retro/renaissance style of very-low-resolution graphics, such as from the 1977-1995 Atari, GameBoy, & Super Nintendo (SNES) eras.

Featuring aesthetics, gameplay, or themes reminiscent of classic video games. Often characterized by pixel art, chiptune music, or mechanics popularized in earlier gaming eras.

Resources for building and relating to User Interfaces, how the user interacts with your program