Sonic Forces is an action-adventure platform game similar in gameplay and style to prior Sonic the Hedgehog games. The player's goal is to liberate the world from the newly established reign of Doctor Eggman. The game features three playable characters: two variants of Sonic the Hedgehog ("Classic" and "Modern") and the "Avatar" (the player's custom character).[1] Each has unique abilities and attributes: Classic Sonic is restricted to side-scrolling gameplay reminiscent of the Sega Genesis Sonic games and can perform a spin dash on the ground and a drop dash in mid-air to gain speed.[2] Modern Sonic's gameplay follows a similar style to Sonic Unleashed and Sonic Colors: he can double jump, perform a homing attack on enemies, springs, and grappling hooks, and a speed boost by collecting White Wisps.[3] The Avatar is created from a base of seven animal types, which each possess a unique ability; they also wield a grappling hook and can equip weapons known as Wispons, including flamethrowers, whips, and hammers. Depending on the Wispon, Avatars can use temporary abilities by collecting a corresponding Wisp type.[4][5] Certain parts see players controlling both Modern Sonic and the Avatar, switching between them as necessary, similar to Sonic Heroes.[6]
The game is split into several themed levels, some of which are based on locations from past games, such as Green Hill Zone.[7] Players must complete each level while fighting waves of enemies, and (with the exception of Classic Sonic) seamlessly shift from side-scrolling to third-person perspectives.[8] Stages are filled with features such as spring boards, rails, and boost pads, and obstacles such as spikes, bottomless pits, and robots. Scattered around levels are golden rings, which serve as a form of health: rings protect players from damage caused by robots or other hazards, though they lose their rings upon being hit; being hit with no rings kills the player. The game does not use a traditional life system, instead deducting from the player's score depending on the number of deaths.[9] Players are given a grade dependent on their performance; an "S" rank is the best and a "C" is the worst.[10] Certain levels feature a boss, which must be defeated in order to proceed.[3] Bonus levels can be unlocked by collecting Red Rings hidden in most stages and players may occasionally receive SOS Missions, tasking them with replaying levels with a specific objective.[11]