Rito Revolto , Rita's skeletal brother, later comes to Earth and, with the help from a group of monsters, manages to destroy the Rangers' Thunderzords and the Tigerzord, which as a result damages the Power Coins beyond repair. Undaunted, they seek the aid of Ninjor , alleged creator of The Power Coins , who gives them new Ninja Coins, providing them with the even more powerful Ninjazords and the Falconzord.
Later, an Australian girl named Katherine Hillard moves to Angel Grove. She befriends Kimberly, and displays an intense affection for Tommy. Later it is found that Rita had captured Katherine and put her under a powerful spell. As a result, she steals Kimberly's Crane Coin, vastly weakening the Pink Ranger whose life force, like that of the other Ninja Rangers, is connected to her Ninja Coin. It is during this time that the Rangers acquire their most powerful Zords ever; the Shogunzords. Eventually, Katherine overcomes Rita's evil spell and returns Kimberly's Crane Coin to her. Having already been disconnected from the coin and with Zordon's declaration that her time as a Ranger has been fulfilled, Kimberly now has a chance to pursue her personal athletic dreams. She leaves to train for the Pan Globals, choosing Katherine to replace her as the Pink Ranger. Though her initial fear and hesitation keeps her from contributing fully to the fight against evil, Katherine eventually becomes both more comfortable and capable of fulfilling her duty as a Ranger.
After several (or, in this case,beginning with" Master Vile and the Metallic Armor ", less) more battles, Zedd and Rita are joined by Rita's father, Master Vile . Following his failed attempts to defeat the Rangers, he reverses time, turning the Rangers into powerless children. These events culminate in the mini-series, Mighty Morphin Alien Rangers which leads to the next incarnation of the Power Rangers franchise, entitled Power Rangers Zeo.