- "If Shogar Tok's insurrection is allowed to succeed, we may lose access to the Perlemian Trade Route. Access from here to the Tion Cluster will be impeded."
- ―Plo Koon
The Battle of Brentaal IV, also known as the Battle of Brentaal, took place five months after the Battle of Geonosis. The Galactic Republic had received information that a Separatist stronghold would be lying dormant for a few weeks opening a window of opportunity, as well that the planet was seceding to the Confederacy. The world of Brentaal IV was a vital link in the Perlemian Trade Route connecting the Core Worlds and the Tion Cluster. Holding this planet would be of great significance to the war effort. The Republic sent what should have been an adequate task force for the job, comprising of four Jedi and a strong compliment of clone troops and air land vehicles, with the entire effort being coordinated by Jedi Master Plo Koon, in orbit.
As it turned out the information was bad, and the Stronghold was alive and ready for action. The Separatists' headquarters were controlled by a Brentaal clan leader called Shogar Tok, who managed to get the planet to revolt and join the Confederacy of Independent Systems. A grand land battle ensued with Republic, and Separatist forces striking, falling back, regrouping, and striking again. When the battle seemed to be turning in the favor of the Separatists, the Jedi Master Shon Kon Ray, who was in command of the air forces contacted Plo Koon. They were outnumbered, and Jedi Master Shon Kon Ray was in favor of a full retreat. The communiqué was barely complete before his ship was shot down, killing him and his troopers.
Jedi Master Shaak Ti, believing that they still had a chance to prevail, sent word to Plo Koon that she was going to attempt to rally the Republic forces at the fortress for one last push. The amount of forces that converged on the fortress showed just how well their chances looked. About four troops found their way to meet Jedi Master Shaak Ti at the entrance to the fortress sewers. They decided that the Republic's best chances laid in the destruction of the fortress' ion cannon batteries and shield generators, that way an airship could do a bombing run and completely decimate the opposition.
As Master Ti's force moved into the fortress, they realized what it really was—a prison. The commotion on the surface had incited a jail break. Master Ti, realizing the need for more troops, guaranteed the prisoners their freedom if they would help her bring the fortress down. The group of prisoners included the hidden Jedi Knight Quinlan Vos, who had been lost to the Jedi council for some years; Sagoro Autem, a Senate Guard gone renegade; and a criminal named Lyshaa, who had been imprisoned on Brentaal IV. Lyshaa was also the one who claimed the life of Ti's former Padawan, Fe Sun.
The force progressed throughout the fortress as long as they could until they had to split up. Quinlan Vos and Autem would go after the guns, the single clone trooper left in the company would go after the shield generators, and Master Ti and Lyshaa went off to capture Shogar Tok.
The gun team was bogged down by a roving guard squad on duty, and participated in a brief fire fight with them before surrendering briefly. Quinlan Vos used his Force powers to turn the tables, and with his sabotage done, the guns were disabled. The clone trooper assigned to the shields was critically wounded by a grenade launcher, but managed to rig his rifle to self-destruct, destroying the generator.
Master Ti had the idea to use Lyshaa to tempt Shogar Tok with her womanly charms. She did, but eventually betrayed Master Ti, and shot her. All seemed lost until Master Ti regained consciousness and killed Shogar Tok. She spared the treasonous team member, who died on her escape in a lightstorm chamber immediately afterward.
A clone trooper who had been present during the battle later participated in an attack on the planet Tirahnn. During the battle there, the Clawdite Separatist spy Braxus Lyn disguised herself as Jedi Master Ezar Elasra, so that she could free the captured Separatist commander Zolghast. Because of Quinlan Vos' actions during the Battle of Brentaal IV, the trooper believed that Elasra had also turned against the Republic, so he sent a team of Republic agents to try and find Zolghast and the false Elasra.
- Jedi: Mace Windu (First mentioned)
- Jedi: Shaak Ti (First appearance)
- Republic 54 (Mentioned only)
- "CIS Shadowfeed Dispatch 14:9:15 Edition" – Star Wars Insider 70 (Mentioned only)
- MedStar II: Jedi Healer (Mentioned only)
- Yoda: Dark Rendezvous (Mentioned only) (First identified as Battle of Brentaal)
- Labyrinth of Evil (Mentioned only)
- The Official Star Wars Fact File 114 (SHA6, Shaak Ti) (First identified as Battle of Brentaal IV)
- The Official Star Wars Fact File 116 (SHA7–8, Shaak Ti)
- The Official Star Wars Fact File 118 (MAC18, Windu's War)
- The New Essential Chronology (First identified as Battle of Brentaal)
- Star Wars Fandex Deluxe Edition
- The Essential Atlas
- Galaxy at War
- Star Wars: Clone Wars Adventures (Collection: Jedi Battle Logs Vol 1)
- The Official Star Wars Fact File Part 23 (PLO5, Clone Wars Ace Pilot)