Kopaka fell from the sky in one of six capules containing the toa. It would become their mission to free the island Mata Nui, where they washed up, from the grasp of the evil Makuta and save Mata Nui, the being for which the island is named.
Kopaka has nearly unlimited control over ice and the cold. If he uses a large amount of his power at once it may drain his energy, but he can regain it by absorbing energy from ice and cold. He carries a large ice sword capable of freezing anything it touches, including fire, and a small sheild. He posesses the Great Kanohi mask Akaku, the mask of x-ray vision. It allows him to see through walls and also see great distances. The only material it cannot see thorugh is solid gold. He is composed of the biometel known as protodermis. He can withstand extreme cold.
Kopaka was a member of the toa team including Gali, Pohatu, Onua, Tahu, and Lewa. They arrived on Mata Nui unaware of who they were. They found villages of beings called Matoran who had awaited their arrival to free them from the tyranny of the Makuta. The Matoran were led by wise beings called the turaga who knew the toas' names and purpose. It was their destiny to find all of the great Kanohi masks and use them to defeat Makuta who had polluted the minds of the animals of Mata nui, known as Rahi, and put the Great Spirit Mata Nui to sleep. Tahu became the leader of the team.
In their first journeys throughout the island Kopaka gained five other masks aside form his mask of shielding. They gave him the powers of underwater breathing, Sheilding, super speed, super strength, and levitation. At the temple Kini nui the six masks were combined into one golden mask that allowed him to use all of his mask powers at once.
The toa descended to the deep tunnels of the island where they faced shadow versions of themselves, created by the Makuta. They were victorious and reemerged and finished reverting the rahi to normal.
The toa later faced the threat of the bohrok swarms, mechanical bugs that functioned as suits for the krata. The toa gathered one of each kind of krata and used them to unlock and activate the exotoa, power suits of armor. It was Kopaka who discovered the need to do so. They then used these suits to battle the barahg twin queens. At the end of the battle they took off the armor to unite and use their combined power to imprison the bahrag. The resulting energy burst threw them into pools of energized molten protodermis transforming them in to the toa nuva.
Kopaka nuva lost fivew of his masks in his tranformation leaving him with only the x-ray vision mask. Their energy however turned the mask into the Akaku nuva, increasing its abilities and allowing him to share the power with those near him. His ice powers were greatly strenghtend. His sword became a doble ice swor dhta he could seperate and use as skis. His sheild was larger and more durable.
Shortly after, the Bohrok kal attempted to free the bahrag. The toa battled the bohrok kal underground. They were able to stoop them when Tahu nuva slowed down time. It gave the others a chance at getting past the bohrok kal's defenses and they failed to revive the bahrag.