The Grand Guard, also referred to as the Grand Serkonan Guard, serves as both the military and City Watch in large cities on the isle of Serkonos, akin to a gendarmerie. The Duke of Serkonos has his own group of guards, led by "chosen officers".
Like Dunwall's City Watch, the Grand Guard carries pistols, swords, and pouches. Firearms usage doesn't appear to be limited to officers; enlisted guardsmen are sometimes seen carrying and using pistols as well.
Members of the Grand Guard have differing uniform colors (red, white and blue). The color likely denotes specific branches or positions. Members of all ranks may wear protective helmets.
Ranks and Positions
- Guards: They are regular troops and seem to made up of only male guards. They wear short-sleeved blueish-green tunics, beige pants, white belts and bandoliers, and are equipped with swords. There are two distinctive types of regular guards. The first group consists of guards who do not have any shoulder badge nor rank insignia, except for a "Karnaca" badge on their left sleeves. They also wear small backpacks and what appear to be rolls of blanket. Guards belong to the second group have cross-sword shoulder badges, rank insignias on the right sleeves, and wear tall white caps with silver Karnaca badges at the front. These guards sometime augmented their uniforms with masks and goggles, particularly those stationed in Dust District, or black leather vests. Regular guards include the ranks of corporal, sergeant, and lieutenant.
- Elite Guards: They are officers within the Grand Guard, assigned to command areas. Elite guards are well trained in the use of their sword and pistol. In contrast to regular guards, they wear red jackets over beige pants, silver helmets, and white belts with silver buckles. Elite guards include the rank of captain.
- Veterans: They are senior officers. Much like elite guards, they carry a sword and pistol. Veterans have similar uniform to elite guards, except for a few distinctive features. They wear golden helmets with red plumes on top, and dark brown pants. Their belts are also white but brighter, and with golden buckles. Veterans include the rank of major.
- Around 1828, the Grand Guard was sent to the city of Dunwall to hunt for the fugitive Billie Lurk, who had murdered a son of the Duke of Serkonos, Radanis Abele.
- The Grand Guard differs from Dunwall's authorities in that the latter city's Army and City Watch are technically separate organizations, whereas the Grand Guard fulfills both military and law enforcement duties.
- In his younger years, Corvo Attano served in the Grand Guard as an Officer, "demonstrating amazing talents." 
- The model for the guards used in the reveal trailer was made by Hasan Bajramovic for Blur Studios.
- The Grand Guard has both male and female members in its ranks.
- Although the reveal trailer seemingly depicts regular guards using pistols, regular guards do not use pistols in the actual game.
- Before the release of Dishonored 2, it appeared the Grand Guard was called the Grand Serkonan Guard. In the game, the former is much more prevalent.
- Retired Veterans receive no pension pay. This is a point of some consternation among the Grand Guard.
- Unlike the Dunwall City Watch, there is no known equivalent of Watch Lower Guards in Serkonos.