Arboretan
From Tardis Wiki, the free Doctor Who reference
The Arboretans were a sentient plant-like humanoid species native to the planet Arboreta.
Arboretans existed partly outside of time. When an Arboretan died, their consciousness travelled back to its birth and it lived its life over again, trying to fix mistakes they had made until they achieved the best life possible. They called this "the path of perfection". This ability only allowed them to make minor changes, and thus they were unable to prevent Koel Paddox causing their genocide with his experimentation. (PROSE: Festival of Death)
