Katherine "Kat" Hillard (later, Katherine Hillard-Oliver), Kat initially appears as a minor character, passing the series, Kat was ambushed by Rita Repulsa and put under a spell, becoming a temporarily ally of the Evil Space Aliens , she served as the main antagonist of the two-parter "A Ranger Catastrophe", and becoming the monster Katastrophe, served as the central antagonist until she's freed from Rita's spell during the three-parter "A Different Shade of Pink". After being saved by the Power Rangers, Kat decided to become the second Pink Ranger of the 'modern era' of the Mighty Morphin Power Rangers, and the second Pink Ninja Ranger of the Ninja Rangers.
Later when the team discovered the Zeo Crystal, Kat was chosen to become Zeo Ranger I - Pink of the Zeo Rangers.
During the events of Power Rangers Turbo, Kat becomes the first Pink Turbo Ranger of the Turbo Rangers; she eventually gave her powers to Cassie Chan and retired as a Ranger.
Retroactively, Kat is also referred to as the Mighty Morphin Pink Ranger or Pink Mighty Morphin Ranger, as well as Zeo Pink Ranger or Pink Zeo Ranger, though these are in reference to the show, as opposed to proper labels. She has also been labeled Turbo Pink Ranger, a variation on her in-show label.
Many years later, Kat returned in Power Rangers Super Ninja Steel as Tommy's wife and J.J.'s mother, along with other Legendary Rangers, helping the Ninja Steel Rangers against Lord Draven and his army of Robo Rangers.
Five years later, Kat returned in Mighty Morphin Power Rangers: Once & Always as the Pink Ranger again after Kimberly Ann Hart was captured by Robo-Rita and Bandora Protocol was activated. Kat joined her fellow Mighty Morphin Rangers and took part in the final battle against Robo-Rita and avenging Trini Kwan’s murder.
