Bridge Four
Bridge Four was a group of slaves owned by Sadeas on Roshar. They formed one of his many Bridgecrews.
Notorious for its bad luck, Bridge Four seldom kept a bridge leader for more than a few days and almost always took the highest casualties on bridge runs.
A transfer to Bridge Four was often used as a punishment for bridgemen, and the existence of a group worse off than themselves was a mental control used by Sadeas' men on the rest of the bridge crews.
Upon arrival at the bridge yard in Sadeas' war camp Kaladin managed to earn the immediate enmity of Gaz, the lieutenant in charge of the bridge crews, who then placed him in Bridge Four. Kaladin spent several weeks on the bridge crew before deciding to give leading and protecting one more try. Once the decision had been made he quickly turned Bridge Four around, and through his efforts it became the best of the bridge crews, taking the fewest casualties, treating its wounded and training for escape.
During the battle of the Tower Bridge Four rescues Highprince Dalinar resulting in Dalinar buying the freedom of all the bridge crews, placing Kaladin in command of all bridgemen that choose to become soldiers, and requesting Bridge Four as personal bodyguards.