Ryo first thought up the concept for the Silent Hunter after the four came to the Golden City. After they found the Watch Tower and retrieved the code brick within, Ryo then acted on his idea. This created a flying Battle Machine equal to the Sky Guardian and the Silent Hunter was given to Hikaru.
The Silent Hunter is a massive white Battle Machine with blue parts scattered about. It's primary weapon is a massive four-bladed sword that can cut through the Mobile Devasator's wheels with ease. It is also armed with a large blaster cannon with two barrels as well. The Silent Hunter is also able to enter Stealth Mode, making it invisible to all forms of detection.