Mewtra

Mewtra was the first White Mighty Morphin' Poké Ranger in Mighty Morphin' Poké Rangers.

Pre-History (before MMPR)
Mewtra was literally born as a half Mewtwo, half human 10,000 years right before the Great War between Rayquaza and Mariah began. He was literally tourtured by other humans and surprisingly, the other Pokemon. Why? He was different and not like a normal entity. The only one that was his friend was Asuka of the Psychic tribe. She told him about his past and that Mariah sealed him away before she was sealed by the other tribes.

Mighty Morphin'
Appearing in Chapter 43, Amii is captured. Amii's Abra Coin is used to unlock Mewtra, who was serving Mariah at the time. By the end of the first season, he became one of the good guys. He served as the main ally for most battles when Dawson and Mariah attacked in Season 2. His Ecliptazord was one of many machines used to help defeat them. However, in the second movie, Mewtra finds his own source of power, the White Mewtwo Morpher, making him a ranger in the movie and a full-time ranger by the beginning of the third season.

In the second movie, he picked up the White Mewtwo Morpher, which was consumed with evil becoming the White Mewtwo Ranger. However, during the movie, he was able to overcome the evil and he obtained the power of the Omega Psy Phoenix, one of the three great Ninja Zords that was mentioned. After the movie, he had some storylines that focused on him during Season 3. In Chapter 96, Mewtra was faced dealing with his clone to prove his innocence against the rangers. During the season, he meets Erladein, his rival who captures the Omega Psy Phoenix in Chapter 106.

Guest Appearances
Mighty Morphin' Poké Rangers Chapter 130: Prophecy Fulfilled 

Cameo Appearances in Poké Rangers Overtech Overdrive