Similar to the previous title, Sonic Generations, players can play as two variations of Sonic the Hedgehog: Modern Sonic and Classic Sonic. Modern Sonic plays through three-dimensional stages like those seen in Sonic Unleashed and Sonic Colors, while Classic Sonic’s gameplay features 2D side-scrolling stages reminiscent of the Sega Genesis-era of games. Modern Sonic is able to perform homing attacks and can boost by collecting White Wisps, while Classic Sonic, in addition to his Spin Dash ability, can perform the Drop Dash move which was first introduced in Sonic Mania.
In addition to the two Sonics, Sonic Forces introduces a third character, known as the “Avatar”, in which players are able to create their own custom character, a first for the series. The Avatar is created from a base of seven animal types, each of which possesses a unique ability. All Avatars wield a grappling hook that allows them to perform a homing attack, as well as latch onto special hooks to access new areas. Avatars can also equip weapons known as Wispons, including flamethrowers, whips, and hammers, to attack enemies. Depending on the Wispon equipped, Avatars can use temporary abilities by collecting a corresponding Wisp within each stage; e.g. if the Avatar is equipped with the Burst Wispon, they can activate Burst Wisp abilities. Players can unlock new Wispons and customization items as they progress. Additionally, there are “tag team” stages that play similarly to Sonic Heroes, in which players can alternate between Sonic and the Avatar and occasionally use combination techniques.
Players run at high speeds around levels filled with obstacles and elements such as spring boards and boost pads. Levels are populated by robots and other hazards created by series antagonist Doctor Eggman. Scattered around levels are golden rings that serve as a form of health: rings protect players from damage caused by robots or other hazards, though they will lose their rings upon being hit. Unlike other games in the franchise, lost rings cannot be recollected and players now have unlimited lives.