Sonic Mania is a side-scrolling platform game developed by Headcannon and PagodaWest Games and published by Sega for Nintendo Switch, PlayStation 4, Xbox One, and Microsoft Windows in August 2017. It was announced in commemoration of the 25th anniversary of the Sonic the Hedgehog series, and is inspired by the original games released for the Sega Genesis, featuring remastered versions of stages from previous games alongside original ones. The player controls Sonic the Hedgehog and his companions Tails and Knuckles as they venture to defeat their nemesis Doctor Eggman and his henchmen, the Hard-Boiled Heavies.
Development was led by programmer Christian "Taxman" Whitehead, who had previously worked on enhanced ports of early Sonic games. Art, level design, audio, and additional programming were provided by the independent studios Headcannon and PagodaWest Games, chosen for their work in the Sonic fangame community. The game was met with positive reception, with many critics viewing it as a return to form for the series following a number of poorly-received Sonic games released after the 1990s, praising its faithfulness to the early Sonic games, its level design, and overall presentation, with some declaring it to be one of the series' best entries.