Open fire.
~ OOM-9 commanding the Battle of the Great Grass Plains

OOM-9 was a battle droid commander and a supporting antagonist from Star Wars Episode I: The Phantom Menace.

OOM-9 was charged by Nute Gunray to capture Theed for the Trade Federation. His forces had to struggle against the local Gungan population which caused the Sith Lord Darth Maul to take control of the Federation forces. Two Jedi Knights Qui-Gon Jinn and Obi-Wan Kenobi were sent by Supreme Chancellor Valorum to settle the feud between Naboo and the Trade Federation. They were attacked by battle droids and noticed that they were preparing to invade the planet.

Jinn and Kenobi arrived on the planet's surface to rescue the Queen and her subjects while avoiding capture from OOM-9's forces. The battle droids including OOM-9 were deactivated when Anakin Skywalker destroyed the command ship.