After spending nearly two years in development, the fan-made platformer tribute Sonic the Hedgehog 2 HD has at last seen a demo release for Windows platforms.

Offering "an unofficial, complete overhaul of Sega's franchise classic for the modern world," Sonic 2 HD updates the 1992 Sega Genesis title with redrawn graphics, widescreen support, remixed music, an online multiplayer mode, and the addition of Knuckles as a playable character. The alpha release is playable up to the end of the Emerald Hill Zone.

Though it solicited extensive fan input for its initial planning stages, the project will "continue a closed development cycle" from this point forward, Sonic Retro notes. A release date for the finished product has not been announced.