Jata

Jata was a companion of the Twelfth Doctor. He was an Osumaran.

History
In the 19th century, Jata left Osumare in an alnitak class Q7 starship.

In 1899, he crashed onto Earth in Wyoming. Clint Currie found Jata in the desert. Deciding to "make the best of [the] barbaric world", Jata helped Currie commit crimes. Jata became the mastermind behind a number of big-time hold-ups and robberies. Because the black star on Jata's forehead was unique on Earth, Jata was put on wanted posters that identified Jata as Currie's horse.

Three months after Jata came to Earth, the Twelfth Doctor found his crashed spaceship. He came to town a town that Currie's gang were committing a robbery in. While Currie's gang were robbing a train, the Doctor came to the tree which Jata was tied to. Jata willingly came with the Doctor and the Doctor left a regular white horse with a black star painted on its forehead in Jata's place. When Currie tried to consult the horse on how to escape from the town's sheriff, the horse didn't reply because it was a horse and Currie was caught.

The Doctor then offered to take Jata back to Osumare. (COMIC: From the Horse's Mouth) Along the way there, Jata told the Doctor that he was fascinated by educational systems, which prompted the Doctor to show Jata a school in 21st century England.

At the school, Jata and the Doctor left the TARDIS to find themselves surrounded by zombie-like students. Jata let the Doctor ride on his back and they went to a church inside the school which several teachers were hiding in. The Doctor realised that one of the students was a Mkali and that he had sent out a signal that had interfered with the the brains of the students. The Doctor called the Mkali's mother and told her what her son had done. After the school was saved when she came and took away her son, several students petted Jata. (COMIC: Fear Buds)