Gaigasaurus the Machine Revival

Gaigasaurus: renamed of Legendary Neanderthal Bot.Samuel build Neanderthal Bot who only destroy Gaiarc. In Muta Database He was rare appear in Ancient Land. In anime, Samuel build Neanderthal Bot, but Mikoto built another Neanderthal Bot and taken control Renten and Peter. Destroyed by Samuel's Neanderthal Bot.

Neanderthal Bot birth
Samuel built new Neanderthal Bot and destroy the city. Samuel feel ashamed, but Eureka saying he not his fault. Neanderthal Bot turn promise to Eureka feeling.

Neanderthal vs Muta-Bot
He saw Muta-Bot and taken control Renten and Peter. With a battle, Neanderthal Bot battling Muta-Bot Neanderthal Bot and destroy it easily.