Niko could assume many different forms, including a grizzly bear. He pretended to be dead after the Society of the Evening Star raided Roon's Stronghold and massacred his other servants. However, when Bracken and Kendra arrived at the Stronghold, too late to warn Roon of the Society's attack, Niko showed them his abilities to heal his own injuries and change form. He also told Kendra and Bracken to take whatever they wanted from Roon's armory.
Later, Niko caught up with, Warren, Bracken, and Kendra to assist them in the battle to try and save Civia's life. He arrived in the form of a bear, but he died when Civia did, as she was the last Eternal.
- Keys to the Demon Prison (Fablehaven #5)