Lonka was the fusion of the six Toa Catastras.
He approached Naju after discovering that he had betrayed him by offering his allegiance to Blackout. He was subsequently shot in the head by Naju and killed, although he somehow revived himself soon after (this may have been achieved by using his fudge ability to reform his damaged brain).
He then appeared in front of Metrotitan during his battle with Parkin. He grabbed his neck, but was then punched in the face twice. After Metrotitan then grabbed the TSS Bouncy-Ball and hit Parkin with it, he picked him up and threw him at Lonka, who turned into fudge and powered Parkin up.
It would appear that Lonka sacrificed himself to power up Parkin's body using the fudge that he could turn into, as the fudge that made up Lonka's body was separated into the bodies of the original Toa Yerta, and absorbed.