Happy Wheels is a Flash-based game that can be played for free inside of web browsers. Players have access to a full level editor where they can make their own challenging levels and upload them for others to play.
Some user-created levels employ game mechanics or characters from other franchises like Pokemon, Mario or Dead Space, creating situations that push the boundary of the game's original goal of simply reaching the finish line by moving forward. These and all other levels can be rated by the community so that players can focus only on levels that are well-designed, challenging or unique.
Happy Wheels is well known for its popularity with YouTube gaming personalities and Twitch streamers, who play the game because of its silly but challenging nature, as well as the availability of over 6 million levels.