The PlanetBuster Maximus is a Drek Industries weapon in Ratchet & Clank. It was a giant missile built in the blargian bomb factory on Hoven, carried by a large starship, and designed to destroy a planet for Chairman Drek. When blargian scientists found the perfect orbital position for Drek's new planet which could guarantee optimum temperature all year round, they found that Veldin already occupied the orbit. However, Ratchet and Clank, after viewing Drek's broadcast about the device in an infobot on Orxon, flew to Hoven and used a nearby turret to destroy the vessel carrying it in "Destroy the Planetbuster". Following this, Drek created the Deplanetizer as its replacement.
The PlanetBuster Maximus was a very long, green bomb shaped like a rocket, with orange fluids inside. It was carried below a dark green vessel slightly longer than the bomb, with five turrets on top, three engines, yellow highlights, and antennae across the top. Damaging sectors of the ship revealed it was held together by long black frames. It was also defended by blarg heli-commanders using rockets. When all of the sections of the ship were destroyed, the PlanetBuster Maximus fell harmlessly into the icy waters below.
In the 2016 re-imagined game, the PlanetBuster Maximus never appeared, as Drek Industries used the Deplanetizer from the beginning.