Bubbles is a overgrown common goldfish who grew after being a lab rat for Dr. Moor, a scientist/inventor trying to make a shrink serum. After growing to a extraordinary size, Darwin Oranda Moor decided to make full use of Bubbles. He constructed a mech suit for his fish so he may protect the earth against kaiju threats. However, instead of helping him, Bubbles killed Darwin and declared his independence. Bubbles now wishes to dominate the earth so he can eat as many fish flakes as he pleases.