Team Four was a squad operating as part of the Separatist Droid Army of the Confederacy of Independent Systems. They fought against the Galactic Republic during the Clone Wars in 19 BBY. This squad's base of operations was the planet Mokivj, where they carried out patrols of the local droid factory and cortosis mine.
Serennian Duke Solha assigned Team Four the task of investigating the Separatist freighter Larkrer. Unbeknownst to them, Jedi Knight Anakin Skywalker was secretly using the ship in an attempt to locate his wife, Republic Senator Padmé Amidala, who was on the planet. Skywalker was accompanied by the Chiss Senior Captain Thrawn and the astromech droid R2-D2. While at the facility, Skywalker overheard a group of B1-series battle droids approaching his position, and he assumed that they were the Team Four that Solha had referenced.
The novel Thrawn: Alliances, which was released in 2018 and is the second book in the Star Wars: Thrawn trilogy, penned by Timothy Zahn, mentions Team Four.