Dullahan (デュラハン Dyurahan) are a group from the Information Alliance, specializing in electronic information manipulation.
A Dullahan is a type of unseelie fairy, originating from Ireland and in the form of a headless rider on a black horse, carrying its head under its arm.
The group are comprised of military office workers, all dressed in suits and ties, with parted hair. The group's activities involved electronic system inspection and information manipulation.
As part of their manipulation of an Object's black box, they are rumored to use an information safety device called Dullahan Protect (デュラハンプロテクト Dyurahanpurotekuto) because it effectively involves digitally swapping out the head.
Dullahan arrived following the week-long blockade of Second Venice, in a small submersible to avoid detection from satellites, in order to help the cover-up for Sky Dog(br) 3rd CEB, who had carried out the blockade. As part of this cover-up, they fabricated information to place the blame the incident on a fictional Object and Elite, supposedly a younger Elite who had looked up to "Oh ho ho".