Reapers

[close] Reapers were beings linked to time itself. They searched for temporal paradoxes. If the balance of time was disrupted, they would be drawn out in force to remove the offending element. Altering a fixed point in time, or causing the Blinovitch Limitation Effect could draw out the Reapers. Normally, the Time Lords would prevent the appearance of the Reapers and repair the damage to time. However, following the Last Great Time War, the Time Lords were forced to hide out at the end of the universe to prevent another Time War, leaving time more vulnerable to the Reapers as only the Doctor was left to handle repairing the damage.

The Reapers were flying gargoyle-like beings with red eyes, two wings, two claws below their wings that could break through stone, mouths on their chests, tails that resembled a scythe and dark brown, tough scaly skin. They lived in the Time Vortex. The Reapers would search out disturbances in time, such as temporal paradoxes, leave the Time Vortex and act "as bacteria taking advantage of the wound" by devouring everything in the area. Older objects were stronger against them and sentient beings were of more interest than inanimate objects. They devoured creatures through their mouths, leaving no trace. They also released a golden glow from their eyes and under their skin when attacking, or about to attack. Reapers had the ability to deactivate TARDISes as to not allow for an escape from their traps. They could also break their ways into the TARDIS interiors to reach those inside. Reapers could be defeated by making contact with a TARDIS key.