From Halopedia, the Halo wiki
Nightmare Armor was an online group who built accurate replicas of armor from video games, including the MJOLNIR. Their talents were spoken of by popular Halo fan sites, such as Halo.Bungie.Org. Rooster Teeth mentioned them in the audio commentary of Red vs Blue season two, referring to fans wearing red and blue Nightmare Armor suits. G4 has shown them on their shows Pulse, Screensavers, Attack of the Show, and on various E3 promotional spots.
Formed in August 2003 as Nightmare Armor, with 6 members: Sid Garrand, Justin Williams, Caleb Hunter, Michael Allday, David Castro, and Jay aka. Crovax.
In 2005, Microsoft purchased 53 full armored Master Chief costume suits from Nightmare Armor for use internationally in promotions.
In 2007, they made a huge splash with the debut of their Gears of War armor. The debut held at Epic Games was a surprise to all but Mark Rein, the vice president of Epic Games, who arranged the event.
By 2008, all original members had left, citing differences with Sid Garrand.
In 2008-2009, a failed reality series based on the then current group, entitled: Nightmare Armor Shop, was filmed by G4 and Warren Miller Entertainment. The pilot was shown on G4TV and Spike TV. The pilot is no longer shown as Sid Garrand threatened legal action against Warren Miller to prevent the show from airing.
Their relations with Halo.Bungie.Org were strained when Sid Garrand threatened legal action against them for posting pictures he had sent to them in an e-mail in July 2005. Microsoft, however, effectively shut them down serving them with three different cease and desist orders for copyright infringement. However, Bungie was appreciative of their promotion and dedication, as they give them a mention in the special thanks section of the credits in Halo 2.