Blue-Tark was a feminine T-series tactical droid that served under Master Geneticist Zeta Magnus. In 22 BBY, during the first weeks of the Clone Wars, the droid was stationed within the citadel of Marat V during her master's conquest of the planet. Assisting the clone of Zeta Magnus as he controlled the planet as a proxy for his progenitor and creator, Blue-Tark fled the citadel in the wake of the revolt by the native S'kytri, maiming the clone in the process as he stood in the wake of the droid's ship's engines. Returning to her true master in the hear of the Dark Worlds at the Rennek palace, she reported to him of the loss of the world at the hands of the Jedi.