Kelper Shellcracker Three is a Crabcavator.
After Scraptors took his shell, he wants to be in the ocean to find some platinum bearing pearls to make his new shell. In the episode "Crabcavator", Dozer tells Kelper Shellcracker Three that he hates being in the water because of the Aquadons.
He finally got a new shell and thank to Dozer for convincing him about the land.
In "Ore Hunt", Kelper helps Dozer to find any purple ore in the sea. He then starts digging out shows Dozer sea ore but he shakes his head as in no.
He then returns in "Ty vs. D-Structs", where he helps fight off D-Structs and D-stroy with the other Dinotrux, and punched D-Stroy to the tunnel, where D-Stroy got kicked out through the tunnel.