Dino Arch, alias Shieldsaurus, functions as a Dino Weapon character. His base form manifests as an Archelon, a prehistoric sea turtle granting him aquatic mobility. He transforms into the Arch Bone Shield, defensive equipment designed to attach to other Dino Knights for protection. This shield initially serves Dino Tyranno in battles against the Dragozaurs. Following Dino Tyranno's upgrade to Ultimate Dino Knight, the Arch Bone Shield is reassigned to Dino Brachio, and Dino Icthyo employs it briefly at least once.

Discovered alongside fellow Dino Weapons on an island, Dino Arch faces abduction by a thief named Gomez. Intervention by the Dino Knights helps him and the others recover their memories. Upon liberation, Dino Arch utilizes his transformation to escape confinement, immediately joining the conflict against the Dragozaurs.

A notable personal dimension involves Dino Arch developing romantic feelings for fellow Dino Knight Dino Icthyo, whose creature form is an Ichthyosaurus; this connection forms after her debut. Within the Dino Knights team, Dino Arch operates primarily as a defensive specialist, focusing his efforts on providing shield support during combat operations against the Dragozaurs.