Gear Titan

The Gear Titan is the combined Super Machine System robot form of the BioBuddies and the first three Gear Beast Battle Machines combined with the command "Activate Combine Operation!". The heads of the BioBuddies form the control panels for the robot & other combined forms.

Arsenal
The Gear Titan is armed with the Gear Boost Sword, which has pieces of the Rabbit Helicopter on the Cheetah Racer's sword. On it's left arm is the Rabbit Helicopter's helicopter blades, which can create a (albeit very small) force field to protect itself from damage.

The finisher of the Gear Titan is the Dimension Crash, where the wheels & rear amplifiers of the Gorilla Truck emit a field that paralyzes the Viratron Upgrade in its tracks, then slashes with the energy-powered Gear Boost Sword.

Later in the series, Douglas was able to complete the new Viratron Upgrade, the Viratron Delta Upgrade, which was capable of stopping the Dimension Crash. However, this is solved through a new finisher move, Explosion Kick, where it concentrates its energy onto one of its feet to perform a destructive kicking attack at the enemy.

Mega Gear Titan
The combination of the Gear Titan & Gear Hercules.

Trivia

 * In Gear Beasts Return: Lab Rats vs. Power Rangers, this robot is called the Gear Beast Megazord by the Gear Beast Rangers.