Complex sentence: One was built by Obi-Wan Kenobi, who designed it from a whip he had seen a bounty hunter use and it was used by the Nautolan Jedi Kit Fisto and himself during their mission on Ord Cestus.
Split into simpler sentences: One was built by Obi-Wan Kenobi, who designed it from a whip he had seen a bounty hunter use. It was used by the Nautolan Jedi Kit Fisto and Obi-wan during their mission on Ord Cestus.