Chagaska

The Chagaska was a creature that the Immortal God Zellin created from Tahira's nightmares.

It was very large and muscular, with extremely long arms, and finger-like claws. Despite its long arms, it was primarily quadrupedal and walked on its knuckles. According to Tahira, it liked its victims more when they struggled.

Its body was covered in dark brown fur and its face was partially monkey-like and its snout was almost skeletal.

When Tahira gained control over her fears, she also gained control over the Chagaska, taking it from Zellin. She then trapped both Zellin and Rakaya with the Chagaska. (TV: Can You Hear Me?)

Undated Events

A Chagaska was imprisoned in the Judoon prison, along with the Thirteenth Doctor, in the cell behind "Angela" the Weeping Angel. We only see it when the view of the prison is from above, and we see it roar. (TV: Revolution of the Daleks)