I would love to do fangame with Sonic the Hedgehog like Super Mario Odyssey,but within 3D graphics and 2D level sections(such gameplay fusion)with exception of 16-bit sega mega drive/genesis songs(original sonic 1 sprites-running and jumping fast),including boss fights with Zeti,unlockable Station Square,spinning animations similar to Sonic Adventure gameplay mechanics,collecting something similar to emblems,costumes changing…etc.as unlockable level map instead of nes songs and 8-bit pixelart sprites(jumping a lot) boss fights with Broodals,making sommersalts animations similar to Super Mario 64…etc. But how can I do such a Sonic fangame?