Eilis commands the Kadrian army, dedicated to freeing their master, Lanancuras. His body is composed entirely of quicksilver metal, granting him extensive shapeshifting abilities. He liquefies, alters his form, and manipulates his substance into weapons or defensive structures. Eilis extends his quicksilver form over vast areas, transforming and controlling entire landscapes. This power converts surrounding matter into metal, enabling him to forge massive constructs like the Metallisaur—a beast crafted from converted environmental material that fights for him.

Prideful and sadistic, Eilis relishes combat and employs ruthless tactics, including hostage-taking and torturing defeated foes. His loyalty to Lanancuras is absolute, driving him to eliminate any perceived threats to his master’s revival through deception or brute force. In the series' second season, Eilis orchestrates an elaborate trap by disguising his liquid metal body as an amusement park—the "Shinzo Dream Center"—to isolate and ambush the protagonists. He maintains this illusion until the heroes are distracted, then collapses the facade to reveal their true location on a desolate plateau. His primary focus becomes neutralizing Mushra, attacking while Mushra is severely weakened.

As a Kadrian, Eilis accesses a Hyper Beast transformation, evolving into a more monstrous and powerful version of himself. This form amplifies his combat capabilities, though he remains vulnerable to sufficiently potent opponents. His role concludes when the amusement park illusion is breached. His assault on Mushra is interrupted by the arrival of Mushra’s allies, leading to a confrontation that results in Eilis’s defeat.