Door-Ju

"Open your Door!"

- Activation announcement

"Charge!"

- Recharging announcement

"Hissatsu: (Shift Car), Full Throttle!"

- Finisher announcement via Drive Driver

The Door Gun (ドア銃) is a firearm weapon wielded by Kamen Rider Drive, resembling the driver-side door from Tridoron. It first appears in episode 8. When summoned, it comes from the front portion of Tridoron's hollow section. Like the Handle Sword, Shinnosuke names this weapon and Mr. Belt disapproves of the lackluster choice.

Usage
The Door Gun can fire several shots before needing to be reloaded, which is easily accomplished by opening and closing the door. If the door is open while being fired, the Door Gun will give an error announcement of "Open Door" (半ドア) and not fire a shot. Once reloaded, it will say "Charge" (チャージ). If the door is open and closed multiple times while there is still ammo, the bullets will become much stronger.

By turning the Advanced Ignition on the Drive Driver, the Door Gun can project an energy shield from the Door Gun that resembles a car door.

Finishing attacks
The Door Gun can initiate Full Throttle Rider Shooting finishers by loading Shift Cars into the Shift Landing Panel (シフトランディングパネル) slot behind the door after turning the Advanced Ignition on the Drive Driver, with different attacks being performed depending on the car used.
 * Speed: Drive fires several flaming shots, then accelerates them by kicking a energy wheel that forms on the side into their path, slamming into their target at terminal velocity.
 * Fire Braver: Drive fires a beam of energy that resembles the Ladder Expander, which grabs the target and pins them to the nearest wall, then pulls the trigger to detonate the energy construct, taking out the target as well.
 * Rolling Gravity: Drive fires a ball of energy that resembles the 10-ton Weight, which flies over to be directly above the target, then pelts them with a series of bullets before the energy construct falls like a rock, detonating as it hits the target.