Forza Horizon is the fifth game in the racing series, but it's considered an arcade spin-off rather than a true simulation entry. It introduces an open world concept similar to Need for Speed: Most Wanted (2012), Burnout Paradise, and FUEL. The game is set in Colorado, USA, where players participate in the fictitious Horizon Festival with a light story. The festival acts as a central location on the map that serves as a hub for buying new cars, signing up for events, getting paint jobs, etc.
The player starts as one of 250 competitors and has to make their way up by participating in races and gaining popularity. Competition is divided into different Horizon Event tiers represented by wristbands of different colors that need to be earned to progress. Events include point-to-point races, circuit races, rally tracks, illegal street races, skill challenges, speed trap records, and more.
The game features a day and night cycle, off-road racing on dirt tracks, AI traffic with a more forgiving crash system, and a looser atmosphere with announcers, rivals that shout one-liners, radio DJs on three stations, and an audience at the festival. The player must earn street cred by participating in sponsor challenges that involve aggressive driving acts such as drifting, jumping over obstacles, near misses, trading paint, passes, burnouts, drafting, or driving on two wheels.
The series' paint job creator is still present, along with players trading and selling liveries. Performance upgrades can be done manually or automatically, and the game provides a warning when the player attempts to join a race with a vehicle that's not powerful enough. The difficulty is determined through a global and opponent difficulty level, braking, steering, traction control, toggling shifting, and more.
Multiplayer includes regular races through different lobbies based on skill level, King games of tag in open environments, Infected where one player has to hunt down survivors to infect them, and cooperative challenges in a free-roam mode with the entire game world. A final game mode is called Cat and mouse, where players are split into two teams with one mouse each.
In single-player, there are different outposts that act as smaller hubs, offering PR stunts that can be completed to reduce the cost of fast travel between outposts. The Kinect peripheral is supported through its voice recognition capabilities, allowing players to activate GPS and other features while driving.