Play Metal Sonic 3 & Knuckles (Beta) Online

Metal Sonic 3 & Knuckles (Beta) is an unreleased prototype for the Sega Genesis, developed by Sega Technical Institute. It represents an earlier, incomplete state of what would become Sonic & Knuckles, offering a glimpse into the game's development during the platform's later years.

You control Metal Sonic, navigating through unfinished level geometry and experimental stage layouts. The main objective involves progressing through these rough zones, which often feature incomplete visuals, missing collision, and occasional soft locks. Signature mechanics include accessing debug mode to warp between stages and encountering unused enemy behaviors or physics glitches. The pacing is erratic due to the unfinished nature of the build, with some sections playing smoothly and others halting progress entirely. It feels like exploring a digital construction site, where every glitch reveals a piece of the game's hidden history.