Mission to Utapau

At some point late in the Clone Wars, the Jedi Master Obi-Wan Kenobi and the Jedi Knight Anakin Skywalker traveled to the planet of Utapau on a mission to investigate the death of the female Jedi Master Tu-Anh. While investigating, they discovered a Separatist conspiracy to create a powerful weapon using a massive kyber crystal. The two infiltrated the base of those dealing in the crystal and briefly claimed it, but it was later claimed by General Grievous. The Jedi pursued and eventually reclaimed the crystal, learning from Yoda that it was a powerful artifact of ancient legend.