Games Done Quick has raised over $121,000 for charity in less than 24 hours on the first day of a week-long livestreaming event.

Awesome Games Done Quick 2015 (AGDQ) is operated by a 501(c)(3) nonprofit organization that showcases skilled gamers completing “speedruns” of various games.

In gaming, speedrunning refers to beating a game in the shortest amount of time possible. It requires a high level of skill and often exploits bugs and glitches to bypass certain aspects of the game to shave off as much time as possible. AGDQ 2015 has several categories of speedruns, which include Any% (fastest possible), 100% (fastest possible with 100 percent completion), and Low% (fastest possible using the least amount of items or upgrades).

The event also offers “donation incentives” that promise to offer different types of content if certain donation goals are met. These can include having the speedrunners play fan favorites or especially difficult games. Some incentives also require the players to beat the games in a certain way, such as making two people play with the same controller on The Legend of Zelda: Majora’s Mask.

AGDQ 2015 features dozens of games spanning roughly 30 years of gaming history. Some of the games on the schedule for the speedrunners include:

• Contra (1987)
• Super Mario World (1990)
• Battletoads (1991)
• Duke Nukem 3D (1996)
• Silent Hill (1999)
• Portal 2 (2011)
• Dark Souls 2 (2014)

The charity also has a tie-in with HumbleBundle.com, who is offering several of the games showcased on the AGDQ speedruns with the proceeds going to the Prevent Cancer Foundation. The games come with Steam redemption codes and are sold on a “pay what you want” basis. Higher donations unlock different tiers of content, with the top tier of $30 or more currently including seven games, two DLC packs, a 30-day Twitch Turbo subscription, a 3-month Xsplit Premium subscription, and a merchandise pack containing t-shirts, buttons and other goodies.

The event itself is taking place in Herndon, Virginia, and fans can purchase a $50 pass (now $60 with late registration fee) to come watch the speedruners play live.

Games Done Quick’s previous events have raised hundreds of thousands of dollars for other charities, including Doctors Without Borders. AGDQ 2015 supports the Prevent Cancer Foundation and runs through January 10.