Metal Coola is the transformed form of Cooler that appears as the primary antagonist in Dragon Ball Z: The Return of Cooler. After Cooler was defeated and seemingly killed in his previous encounter with Goku, his brain was absorbed by the remnants of a sentient spacecraft computer system known as the Big Gete Star. Fusing with this entity, Cooler took control of the system and rebuilt himself with a fully mechanical, metallic body composed of a silver alloy that mimics his original appearance. This new form allows him to remotely command an army of mass-produced cyborg clones, also called Meta-Coolers, which are controlled from the core of the Big Gete Star and act as decoys before the true nature of his survival is revealed.

Metal Coola retains the same cold, arrogant, and ruthlessly pragmatic personality he possessed as a biological being. He is driven by a desire for revenge against Goku and the Saiyans, as well as an insatiable hunger to absorb planetary energy and lifeforms to fuel the Big Gete Star and sustain his own existence. His motivations are purely self-serving: he seeks to convert all living matter into power for his ship and himself. In the story, Metal Coola invades New Namek, latching his ship onto the planet and terrorizing the Namekian people. He confronts Goku and later Vegeta, showcasing his newfound abilities and overwhelming regenerative capacity. His relationship with Goku is defined by bitter enmity, as Goku was responsible for his prior defeat. With Vegeta, Metal Coola shares a brief but intense rivalry, as both Saiyans must cooperate to overcome him. The clones are mere extensions of his will, displaying a hive‑mind mentality and absolute loyalty to the original Cooler core.

Metal Coola undergoes no significant character development within the film; he remains a static, vengeful entity whose main evolution is the transition from organic to cybernetic existence. His notable abilities include instantaneous movement, which he uses in combat similarly to Goku's own technique; rapid regeneration, as his ship constantly monitors and repairs damage to his metal body; and the mass replication of Meta‑Cooler clones, which can number in the hundreds or thousands. He can also absorb the energy of an entire planet and its inhabitants to power himself. His core weakness is the biological Cooler that still exists within the Big Gete Star’s central system, which ultimately allows Goku and Vegeta to overload the system with their combined ki, destroying the true Cooler and causing all clones to disintegrate.