Krafayis

The Krafayis were a species of space-faring omnivorous predators.

Biology
The Krafayis were large creatures, with both reptilian and bird-like traits. They had parrot-like beaks, a quill-like horn, two wattles on the side of their heads, long necks and quills down their tail.

The Krafaysis were generally invisible, allowing them the perfect defence. They could be seen by Vincent van Gogh (apparently due to his unique perception of the world) and in the reflection in a mirror on the Visual Recognition System. (DW: Vincent and the Doctor) They could also be seen in the other reflections, such as in water. (DWA: Blind Fury)



Life cycle
The Krafayis were somehow capable of travelling through the universe, moving from planet to planet to hunt. They preferred to travel to planets with oxygen/nitrogen atmospheres, such as Earth. They hunted in large packs with a strict hierarchy and had territories which spanned star systems. Eventually, they would leave the planet, leaving behind the weaker Krafayis. These Krafayis would be unable to rejoin the pack and in their loneliness would cause destruction and chaos until they were killed. (DW: Vincent and the Doctor)

History
The Krafaysis were believed to be an ancient species. Legends say that in the Old Times of Gallifrey, a Krafaysis attacked the village of Slothe, killing many people. A Gallifreyan, Presus, eventually confronted the Krafaysis and after three days of fighting, the Krafaysis was killed. (DWA: Blind Fury)

At some point before 1890, a pack of Krafayis came to Earth, fed and left. One blind Krafaysis was left behind in France, where it attacked several people. It was also seen by Vincent van Gogh and painted into The Church at Auvers.

When the painting was seen by the Eleventh Doctor and Amy Pond, they travelled back to before it was painted to investigate. During the visit, they saw the remains of one of its victims and were later attacked by the Krafaysis itself. The Doctor was eventually able to identify it and planned to confront it in the church, stunning it with his Sonic screwdriver. This attempt failed, and the Doctor, Amy and Vincent were forced to hide. The Krafaysis followed them and attacked, forcing Vincent to fight back and accidentally kill it. Following this, the timeline was changed and the Krafaysis never painted into The Church at Auvers. (DW: Vincent and the Doctor)