Sonic All-Stars Racing Transformed is free-to-play this weekend on Steam until 1 p.m. PT on December 8.
The game will also be discounted 75 percent, making the game $4.99, until December 9. According to Polygon, Steam is also offering the game in a four-pack for the price of three. The deal nets the four games for the price of $14.99, which is a mark down from $59.99, just in time to purchase gifts for the holidays.
All-Stars Racing will be available for free download on Steam, but will not be accessible after this weekend unless purchased.
Creator's of the game, Sega, are partnering with Yogcast YouTube producers to raise money for the charity SpecialEffect. In a new DLC, Honeydew, who is part of Yogcast, will drive a Sumo Digital cart racer, and will be a downloadable character on Steam for $5.99.
UK charity, SpecialEffect helps children with disabilities play and enjoy video games.
"Yogscast, the UK's most watched YouTube channel, run an annual charity drive for the month of December. This year, they are teaming up with SEGA and taking the drive to the next level in a race against the fastest Hedgehog in the world. The Yogscast's very own Simon Lane, aka Honeydew, is now available as a brand new DLC character in Sonic & All-Stars Racing Transformed™ with 100% of all SEGA and Yogscast proceeds being donated to the SpecialEffect charity," posted Steam.
Sonic the Hedgehog was most recently in Sonic's Lost World last month. Sonic will also be in the upcoming Super Smash Bros 4 as a playable character to battle against Mario and a cast of other Nintendo characters.
Rumors also indicate that a new Sonic the Hedgehog animated cartoon will be coming sometime in 2014.