Grub

The Grub were a species from the planet Safenesthome, but were later forced off-world.

Biology
They had voracious appetites and were capable of eating nearly everything they wanted to. They could excrete gelatinous fluid from their tails, which they could use to stick people onto walls and ceilings, as they did with the Metatraxi. They reproduced by spores which were identical to grain.

History
The Grub were the original inhabitants of the planet Safenesthome, but treated it badly and ended up devouring nearly everything on it, reducing it to a desert planet.

The planet evolved the Metatraxi in order to fight the Grub back, eventually making them leave the planet. They ate even more after this as a way of putting off memories of the traumatic event.

A hatching of Grubs were hidden abroad a shipment of grain being delivered to the planet by the organisation Earth Aid. The shipment was eventually offloaded and the Grub were back on their own planet. Although there was initial hostility from the Metatraxi, the planet had forgave the Grub for their earlier behaviour and ordered the Metatraxi and the Grub to live in peace together.