Dindrinine

Dindrinines were a space-faring avian species encountered by the Thirteenth Doctor.

Biology
Dindrinines were, in their true forms, a race of highly feathered, bipedal bird-like creatures with especially long, sharp beaks and purple skin and feathering. Despite looking fearsome, they were somewhat easily dispatched, with the Thirteenth Doctor fooling them into thinking her boots were prized trophies and being able to stop their beak attack by tying them up in string.

They were also highly adept at disguises, being able to fit into a human-shaped skin suit that was smaller than they were, which would open at the mouth when being taken off.

History
The Dindrinines' Fourth Fleet once engaged in a devastating war that wiped out all but two members: Gebra and Hurum. They were rescued by the Thirteenth Doctor and placed at the Gardens of Everlasting Summer to wait for their rescue ship, but help never came. They were forced to settle down in the gardens by disguising themselves as an elderly human man and woman, respectively. By the time the Doctor encountered them again, she had forgotten all about them, enraging them further to her supposed trickery and leading them to try and kill her multiple times.

Only upon being forced to briefly work together did the Doctor realise that their ship likely missed them during an artificial time storm, and she offered to take them home herself. They then openly regretted their actions, believing they had misjudged her. (COMIC: The Everlasting Summer)