|"My girls are dead, my wife's dead, and I'm sick of the marsh stink. I'm with you."|
|— Nix Marsten to Mare Barrow|
Nix has lost both of his nineteen-year-old daughters, Dara and Jenny, to the war. They were part of the Hammer Legion, a legion whose fate was decided by Cal. As a result, Nix fosters a direct hatred of Cal. He worked as a crabber in his village.
Nix is the first newblood on Julian Jacos' list that Mare, Cal, Farley, Kilorn, and Shade track down. He is first due to his proximity to Tuck Island. He lives in a town called Coraunt on the Marsh Coast region of Norta.
Farley and Shade are elected to sneak into Coraunt and bring him safely to the rest of the group. He recognizes Mare on sight, as well as Cal, whom he proceeds to attack. Mare attempts to electrocute him, but finds his skin invulnerable to her lightning. Shade jumps Nix away from Cal so Mare and Farley can offer him the choice of joining them or staying in Coraunt.
As his wife and daughters are dead, Nix agrees to leave his home and accompany the group to find more newbloods. He develops a quick friendship with Kilorn. He dies in the battle at Corros Prison.
He is gruff, direct, and is a man with no use for secrets. He is still depressed and heartbroken from the loss of his wife and daughters.
He is squat, muscled, and has a round stomach typical of middle-aged men. He has the haunted look of someone that has lost everything. His hair and clothes are both gray and his teeth are yellow.
Nix has the blood mutation that grants him a Silver-like ability despite having Red blood. Nix is an invulnerable, meaning he is unaffected by all physical attacks, including from other newbloods and Silvers. Unlike a Silver stoneskin, his skin remains normal and doesn't turn into stone when he is using his ability.