Drüskelle are holy soldiers from Fjerda who hunt Grisha for trial and execution at the Ice Court. They claim that Grisha are demonic and evil, and use this to justify killing them. Although they say that all Grisha stand a fair trial, it is widely known that they are biased and often end up burning Grisha in pyres. Drüskelle have very hard and regimented training. They work with wolves commonly and once a wolf is partnered with a soldier, they work together as one. If a wolf dies first, it is a terrible loss, but a new one can always be trained. If the soldier dies first, the wolf is returned to the wild, but no pack will accept them.
Their uniforms are black and silver; in training they are grey.
According to Matthias, the drüskelle training process involves hours of running and sparring, presumably every day. An atmosphere of brotherhood is encouraged. At a certain point, drüskelle in training make a journey to the Ring of Stones to choose their wolf companion, the iseunulf. The wolves are paired with the drüskelle as puppies.
The isenulf are the white wolves bred to go into battle with the drüskelle. They are said to be larger than normal wolves but highly trained and can be of great help in a battle, as they fight alongside the drüskelle. According to Matthias, only one family breeds the isenulf, and it is a tradition for drüskelle in training to visit the breeding grounds in the Ring of Stones to choose a puppy. Not all druskelle get an isenulf if there are not enough puppies bred that year.
If an isenulf is killed, the drüskelle may train a new one if he so pleases. If a drüskelle is killed, on the other hand, the isenulf is sent back to the wild, unaccepted by any pack. 
- There is an initiation rite for new Druskelle called Hringkalla.
- "He wore a gray uniform, not the black of a full drüskelle officer." From Crooked Kingdom, page 486
- "He didn't mind the training. The hours spent running and sparring helped to keep the longing he felt for his family at bay." Crooked Kingdom, page 240
- "Brum had warned him that he would never become a true drüskelle if he did not learn to see the other boys as his brothers..." Crooked Kingdom, page 240
- Crooked Kingdom, page 240-241
- Crooked Kingdom, page 239