Grimm (RWBY)

"For as long as humanity can recall walking the surface of Remnant, so do they remember this wicked force."

- Salem in "World of Remnant: Episode 3".

Grimm, or the Creatures of Grimm, are the universal antagonists of RWBY, inhabiting various parts of Remnant.

They are described as "creatures of destruction" and lack a soul; hence, they are unable to use Aura. They are in turn also drawn to feelings of negativity such as envy, sadness, loneliness, and hatred and will often congregate towards the source of these emotions.

At one point, ancient cultures believed that Grimm were animals possessed by evil spirits, or were the spirits of once tortured animals.

History
According to Ozpin, the Grimm were created by the God of Darkness in order to destroy his brother's creations. Grimm have targeted early Humans for as long as can be remembered, seeking to destroy them and all of their creations. At first, it seemed as though they would succeed as Humans did not have the strength to fight them. However, Humans discovered the power of Dust and with it, the Grimm were driven back. During this time, Humans enjoyed a time of peace and soon formed their own kingdoms, which grew to survive and prosper. This time will not last forever, however.

While Grimm are initially mindless and heedless of risk during their youths, to where they will simply attack any humans on sight, some Grimm are so powerful that they have survived to live for hundreds of years, and in that time they have evolved and learned from their experiences fighting humanity. In doing so, they have exhibited restraint and the patience to avoid taking unnecessary causalities in futile conflicts. Instead, they stay close to humanity's borders, waiting for the opportunity to come where they can finally strike, and thus mankind is always in ever present danger, even in times of apparent peace. This was stated by Dr. Oobleck in the episode "Search and Destroy", when he tells Ruby on how intelligent some species, such as the Goliaths, have become over the years.

Additionally, the Grimm appear to be the predominant species in the world of Remnant as humans and Faunus appear to be limited to four primary pocket settlements referred to as Kingdoms, which are guarded by Hunters, as well as several villages with mixed success. Attempts by the Kingdoms to expand beyond their borders are often met with resistance, and even failure, as the loss of an entire sector of the city of Vale overrun by the Grimm can attest to.

Biology
Grimm appear to be born from mysterious black pools, as seen when Beowolves emerge from them in Salem's Domain. However, most of humanity is unaware of the origins of Grimm. Ancient human cultures believed the Grimm were animals possessed by evil spirits, or even the tortured spirits of animals themselves. Further study has disproved this theory over time however, due in part to the discovery of even more horrific misshapen species of Grimm which have no animal counterparts. With the discovery of new types of Grimm every day, scientists are left with more questions then answers.

Grimm come in a variety of shapes and sizes; the latter appears to be a factor of age, and are said to be the only creatures without souls, thus being deprived of the use of Aura, but making up for this with strength and savagery. Grimm are stated to be attracted to generally negative feelings such as sadness, hostility, anger, fear, etc. and even congregate to areas that, although humanity has long since abandoned, still hold residual traces of these feelings.

This behavior will even lead to them to join in on an attack in progress if the humans being attacked begin to panic. Grimm typically form packs or other types of large groupings with other members of their own specific species. While some lone Grimm may stray from the pack for hours or even months, they will inevitably rejoin their group to continue their instinctive drive to hunt the people of Remnant and destroy any artificial creations associated with them.

The longer a Grimm lives, the larger it becomes, with species such as the Nevermore ranging from the size of an average bird of prey to massive pterosaur-sized beasts after hundreds of years. This added size comes with an ability to learn from their encounters in contrast to the Grimm's more reckless nature during their youth. While sometimes requiring hundreds of years, the Grimm's accumulated experiences over the course of surviving their battles with man can cause them to begin exercising caution.

This perverse form of self-preservation can even lead them to avoiding unnecessary conflicts altogether. Yet, despite this ability to learn, their instinctual hostility still remains, as shown by their preference to patrol the borders of Kingdoms for any weaknesses they might someday exploit. This demonstrates that for all their apparent intelligence, older Grimm simply use it as a means to become more effective in their singular drive and purpose, to kill.

Grimm display no enmity towards normal animals, and they only clash during territorial disputes. Humans and Faunus are the only races they attack on sight. Grimm can also choose not to display feeding behavior and it is commonly believed that they do not require sustenance. When Grimm die, their corporeal form evaporates, preventing detailed anatomical or biological studies. Huntsmen that kill for sport cannot stuff and mount Grimm bodies as trophies (making do with replicas instead).

Also of interesting note is that Grimm usually die off when in captivity (if they cannot kill their captors or escape first), implying that they cannot be kept alive by normal means. If the theory of Grimm not needing to feed is true, it is entirely possible that they survive on negative emotions or the act of killing itself.

Volume 1
As part of Beacon Academy's initiation, new students must team up in the Emerald Forest and fight their way to a temple, encountering several different types of Grimm in the process. Ruby Rose and Weiss Schnee are attacked by a large pack of Beowolves, but are forced to flee when Weiss' attack causes a fire due to Ruby's accidental interruption.

Yang Xiao Long is also attacked, but by two Ursai that only manage to sever a strand of her hair, sending her into a blind rage as she defeats one of the Ursa, as the other is killed in one strike by Blake Belladonna before Yang can finish it off. Likewise, Lie Ren is attacked by a King Taijitu, which he defeated through the use of his Aura.

While searching for the abandoned temple, Jaune Arc and Pyrrha Nikos find a cave that they confuse for the temple. While exploring, Jaune grabs on to the stinger of a Death Stalker, believing it to be one of the relics. Pyrrha then runs out of the cave and the Death Stalker follows her out, breaking down some rocks covering the entrance as it does so. Once outside, it flings Jaune, who is still hanging onto the stinger, into the air and Pyrrha flees from the Death Stalker.

The Death Stalker chases Pyrrha to the temple while Ruby and Weiss are carried there by a Nevermore. Upon arrival, they meet up with Yang, Blake, Nora Valkyrie, and Ren, the latter two arriving at the temple via Ursa. The two Grimm chase the eight students to a larger part of the temple where Team JNPR are able to kill the Death Stalker by using a plan devised by Jaune: hacking off its stinger and then hammering it into the creature's head.

Meanwhile, Team RWBY were able to defeat the Nevermore by using Gambol Shroud as a giant slingshot to launch Ruby at the Nevermore. Using Myrtenaster's Dust capabilities and the recoil of Crescent Rose to propel herself, Ruby successfully beheads the creature after dragging it up the face of a cliff. The defeat of the particularly fearsome Grimm using the plans of Jaune and Ruby led to them being made the leaders of their respective teams.

In the first class of Grimm Studies, Weiss, in an attempt to prove herself superior to Ruby, volunteers to take on a Boarbatusk in a class demonstration. In the battle, the Boarbatusk manages to disarm Weiss, but she eventually retrieves Myrtenaster to both block and kill it.

Later on, in the Forever Fall forest, it is revealed that there are larger Grimm creatures of the same name, although in "The Emerald Forest", a larger than normal Beowolf was briefly seen. In "Forever Fall, Pt.2", a much larger Ursa was seen attacking Cardin. Unlike the smaller ones, it had many larger spikes and armor plates on its back. However, it is defeated by Jaune with slight help from Pyrrha's Semblance.

Volume 2
After intelligence is uncovered about a White Fang base in the ruined Southeastern block of Vale, Mountain Glenn, Team RWBY, alongside veteran Hunter Bartholomew Oobleck, is dispatched to the Grimm-infested area in preparation for a full scale invasion to confirm the White Fang's base. Before departing, RWBY encounter Team CFVY, who report that the number of Grimm outside the city are increasing, backing up an earlier warning from Ozpin. The headmaster reminded Team RWBY before they left on their mission that that, normally, students as young as them would not be permitted to confront such large concentrations of Grimm.

The Grimm living in the area seem limited to Beowolves, small Nevermores and Goliaths. The latter seem to prefer roaming the wilderness outside of the ruins. While the girls occupy their time with slaughtering the Grimm, Bartholomew seems to prefer to spend his time studying the ruins, the plant life, and the Grimm, when possible. A Beowolf is briefly seen later during Ruby's watch of their encampment. Later, Oobleck informs Blake, Yang and Weiss that there are also subterranean Grimm.

In "No Brakes", it is revealed that the White Fang are loading the Dust they've been stockpiling onto a train in Mountain Glenn where they rig each train car to separate and explode at timed locations leading to Grimm flooding the subways, with the last of the train cars blowing a hole directly into the city of Vale, thereby allowing the Grimm to enter the city and slaughter thousands. In spite of Team RWBY's best efforts, the plan proceeds leading to the Grimm attacking Vale. After a long and intense battle, the Grimm are finally driven away through the combined efforts of teams RWBY, JNPR, CFVY, the Beacon Academy teachers Peter Port, Glynda Goodwitch, Bartholomew Oobleck and the Atlas Military droids.

Volume 3
The Grimm, drawn to the negative emotion in the city after the death of Penny, breach the defenses of Vale undetected and begin attacking. Goliaths and all manner of Grimm move in as people panic and attempt to flee. Ozpin sends Glynda Goodwitch and Qrow Branwen to the city and calls upon Ironwood to use his army to defend it. In the skies above, Giant Nevermores are attacking Amity Colosseum as well as Ironwood's airships while hordes of Beowolves and Ursai overwhelm the troops on the ground.

As the students in the Colosseum re-group, several Griffons, large flying creatures of Grimm, land on the stadium and begin to attack, but are stopped by Professor Peter Port and Doctor Bartholomew Oobleck. Hundreds of civilians are attempting to leave the Colosseum on Air Buses, but Grimm are being off-loaded at the landing bays by White Fang Bullheads. Alongside his Atlesian Knight-200 androids, General James Ironwood defends the landing area, personally fighting off a large Alpha Beowolf with his revolver. When the students come to Ironwood for guidance, he gives them a choice – either fight and defend their Kingdom and school, or escape and save themselves.

However, the ground below begins to tremble. An enormous Grimm Dragon awakens and erupts from beneath a mountaintop near Mountain Glenn. The beast then takes to the air and heads towards Beacon Academy, spawning lesser Grimm in its wake. Arriving at Beacon, the Dragon becomes transfixed to the Beacon Tower, circling around it repeatedly. Cinder ascends to the top of the tower and begins communicating with the Dragon. She makes eye contact with it and tells it that Beacon is its home now. During Cinder's battle with Pyrrha, the Dragon destroys the top of Beacon Tower, disabling the Cross Continental Transmit System. After witnessing Cinder killing Pyrrha, Ruby Rose unleashes a tremendous power in grief. A blinding white light envelops the Dragon, which is seemingly "frozen" in its place, perched on the side of the tower.

Although frozen, the Dragon remains alive and continues to attract more Grimm to what remains of Beacon. Its enormous inert body is still fully visible from Vale.

Trivia

 * The name for the creatures of Grimm may be a reference to the Brothers Grimm or Grimm's Fairy Tales, a famous collection of German fairy tales compiled by the brothers.
 * Additionally, Grimm is German for fury or wrath.
 * Grimm wear white masks with red blood trail-like designs, similar to the Hollows from the anime Bleach.
 * Grimm follow a color theme of red, white, black, and a little yellow.
 * These are the colors of the four main characters.
 * The White Fang wear Grimm masks because humans tried to make monsters out of them, so they wear the faces of monsters as a symbol.
 * All of the Grimm creatures vocal sound effects were done by William Orendorff, who also voices Hazel.