Death Angel

Origin
Most information about these creatures is unknown. Where they came from is unknown, how they procreate is unknown, and how they eat is unknown.The only place these creatures have been observed on is Earth.

They hunt by their hypersensitive hearing, locating anything that makes noise. They have also adapted to survive in the vacuum of space, hitching rides on meteors to reach their next 'destination'.

They boast an incredible amount of speed, as well as an impenetrable armored shell, and are blind.

Interestingly, if there is a much louder noise nearby, those who speak to each other cannot be heard by Death Angels.

Invasion of 2020
After meteors came in contact with Earth, Death Angels wiped out most of Earth's population over the span of three months. In the first hours of the invasion, military forces from around the globe began to fight back. But the creatures' armored shells proved too strong for bullets, bombs and even bioweapons. Earth has eventually been stripped of its freedom as Death Angels spread to new areas to further decimate the population.

Weaknesses
There is such a thing as a cochlear implant. If turned up to its highest volume, then held up to a microphone, the high-frequency sound will painfully disorient the creature. Enough of these high-pitched sounds can kill a Death Angel, if not render it immobile for a short period of time.

If the frequency is not enough to kill the creature, it will weaken it to a state where firearms can easily kill it.