From Halopedia, the Halo wiki
Halo Fest was an event held by 343 Industries to celebrate the history of the Halo franchise. There have been two official Halo Fest events - one in 2011 and one in 2014 - alongside one held by GameStop in 2010 to celebrate the release of Halo: Reach.
Halo Fest 2011
- Anniversary Map Pack: several maps were announced and ready to play at the event including Installation 04, Ridgeline and Solitary, while Penance and Battle Canyon were playable for the first time in the US.
- Stereoscopic 3D: attendees were able to experience the Halo Anniversary campaign in 3D at the LG Cinema 3D Experience.
- Halo: Reach Title Update: preview of the Halo: Reach Title Update and Anniversary settings.
- Forza Motorsport 4 and Halo 4 Warthog: A preview of the M12 Warthog in Forza 4.
Halo Fest 2014
Halo Fest 2014 was held in the Avalon Theater in Los Angeles on November 10, 2014 - one day prior to the release of Halo: The Master Chief Collection - and the event was livestreamed on Xbox LIVE and Twitch.
- First look at the Halo 5: Guardians Multiplayer Beta: Attendees were able to play the Halo 5: Guardians beta early and see an exhibition match between esports pros.
- World premiere of Halo: Nightfall: Fans were able to watch the first episode of the series.
- Interviews with 343 Industries: Interviews were conducted with Frank O'Connor, Dan Ayoub, Josh Holmes and Bonnie Ross.
- Global Halo Tournament: A launch invitational featuring 32 of the biggest names in esports playing Halo 2: Anniversary for $50,000.
- At the event, attendees were treated with custom chocolate bars called "Master Chocolate".