Death Stalker

Death Stalkers are large scorpion-like species of Grimm.

Appearance
Contrary to most creatures of Grimm, which have black fur or feathers, a Death Stalker has a jet-black exoskeleton underneath several white, bonelike plates upon its back, which are adorned with red markings.

One of the more prominent attributes of this Grimm is the glowing golden stinger on its tail that it uses as a lure. It also has a pair of large pincers that it uses to defend itself and grab/cut into its targets. The Death Stalker's ten red eyes and unique markings can also glow in the darkness when it chooses to reveal itself to its prey.

The Death Stalker encountered in the Emerald Forest has what appears to be moss or grass growing on its claws and torso, indicating that it had been laying dormant in the cave for a long time. It also has visible scars on its carapace, signifying its advanced age. This is further reinforced by the crude drawings made on the entrance to the cave.

RWBY
In "The Emerald Forest, Pt.2", a Death Stalker appears within a cave in the Emerald Forest. Jaune Arc and Pyrrha Nikos walk into the cave, mistaking it for the forest temple. Jaune spots a large, glowing object in the darkness and, thinking it is a relic, tries to grab it.

When he does, the object is revealed to be the glowing stinger of a Death Stalker. This causes Pyrrha to flee as the Scorpion-like Grimm begins pursuit, while Jaune hangs on to the stinger for dear life, screaming in fear. The creature then breaks out of the cave and flings Jaune back into the heart of the forest. Pyrrha prepares to battle, but determines that a retreat is a better course of action.



In "Players and Pieces", the Death Stalker follows Pyrrha all the way to the abandoned temple, on which Blake Belladonna remarks. It then knocks Pyrrha to the ground in front of the others and Yang Xiao Long sarcastically comments with, "Now we can die together."

Ruby Rose takes it on by herself, but is forced to retreat when both the blade and the rounds from Crescent Rose prove ineffective. She is then pinned to the ground by a giant Nevermore's barrage of feathers and is only just saved from the Death Stalker by Weiss Schnee's intervention.

The group retreats to the cliffside. They flee from the Death Stalker across a small bridge, but the Nevermore destroys it, isolating Blake, Pyrrha, and Lie Ren from Jaune and Nora Valkyrie. Eventually Blake is knocked across the gap created by the beast, while Jaune and Nora join the battle. Ren shoots at its tail, but is unable to detach it before he is flung against a nearby wall.

Jaune is the one that comes up with a plan to beat it: recognizing that Ren had weakened the stinger's connection to the rest of the tail, he tells Pyrrha to throw her shield to cut off its stinger. He then orders Nora to use Pyrrha's shield as a launching pad to fling herself in the air, before driving the stinger into the Death Stalker's head with Magnhild. This attack successfully kills it, its corpse falling into the abyss surrounding the cliffside.

A trio of Death Stalkers are seen in Vale, slowly scuttling towards citizens in "No Brakes". Later, in "Breach", a Death Stalker confronts Coco Adel, who promptly backs away, pulls out her handbag, and transforms it into a massive Gatling gun. She then proceeds to shoot it to bits, before turning her attention to the Nevermore above.

RWBY: Grimm Eclipse
A mutant Death Stalker was created in secret by Merlot Industries using a mutation serum. The mutant had unique capabilities, such as firing poison projectiles from its stinger, burrowing underground, as well as the ability to spawn other Grimm. Doctor Merlot unleashed the Death Stalker in a desperate fight against Team RWBY, who were attempting to shut down his operation. However, Team RWBY defeated the mutant, foiling Merlot's plans.

Powers and Abilities
Other than the obvious attacks using pincers, a bite and a sting, not much is known about its attacks as it is yet to perform any. Its stinger appears to glow in the dark, though the exact purpose of this is not known (though it did serve as a lure for Jaune). However, the use of its stinger was only seen once, on Ruby, where it failed when Weiss froze its tail in an ice barrier, saving Ruby. It implies that the Death Stalker uses its stinger like any other scorpion, as a jab for poisoning its prey. However, it is unknown what, if anything, lies in its stinger.

A Death Stalker is also shown to possess immense physical strength, as it was able to shatter the rocks around a small cave entrance in order to escape, as well as many trees of the Emerald Forest while chasing Pyrrha. It was also able to fling Jaune a considerable distance using only its tail.

It also has what appear to be battle scars on its body, signifying it has managed to survive some tough battles. The Death Stalker also seems to have a surprising amount of speed for its size, as it was able to catch up to a fleeing Pyrrha, even though she had a head start.

It is also highly resistant to damage, withstanding bullets from Crescent Rose, StormFlower, and Miló with ease. It has also been shown to resist blades such as Crescent Rose, StormFlower, and Gambol Shroud. However, the armor seems to be weak near its unions, as seen when Team JNPR cut off the stinger of one in "Players and Pieces". Also, heavy artillery seems to be able to pierce through its armor, as seen in "Breach", when Coco killed one with her weapon.

Despite its resistance to damage, the Death Stalker seems to be slightly affected by strong blows, such as those from Nora's Magnhild, which left it disoriented a few times. The only object shown to be capable of piercing the Death Stalker's cephalothorax is the Death Stalker's own stinger, which falls directly into the beast's head after being severed from its tail.

Trivia

 * The cave where a Death Stalker emerges from has old drawings of people attacking the monster with sticks and spears. This could signify that the monster had been in the cave since the original war with the Grimm.
 * This is supported by the creature's aged and battle-worn appearance, which suggests that it is very old.
 * It is also possible that the armor of a Death Stalker grows stronger with time, as the creature has battle scars from previous conflicts but advanced weapons, like Crescent Rose, prove ineffective in damaging it.
 * The initial function of the Death Stalker's glowing tail stinger is very similar to the Anglerfish and its own glowing appendage in reality. Both use it to lure their prey to them via the light on the end of the appendage, before attacking and presumably killing them. Also, their eyes and markings illuminate once they reveal themselves.
 * Death Stalker is also the name of a real species of scorpion.