Sonic Nexus is a
Sonic Fan game for PC Created by Taxman aka Christian Whitehead. the very same one that help remake
sonic 1, 2, and CD For android and IOS, as well as the same one who is currently helping sega in making
sonic mania which by the way is powered by his own engine known as the retro engine which this game is also powered by so in the case if you want a general feeling as to what
sonic mania might feel like, then I would highly recommend trying this out sometime. since 2008, only one playable demo has been released to the public and haven't been worked on ever since so in the case if any of you wants to get this for yourself, here's a link.
Sonic Nexus [SAGE 2008 Demo]