Wesen in the G category.

Gedächtnis Esser:

A Gedächtnis Esser (guh-DAY-KHT-niss ESS-er) is an octopus-like Wesen. Gedächtnis Esser use four tentacles of their tentacles when waged (look below at Features) to burrow into the back of their victims' heads to steal their memories; exactly how it works is unknown, but it is theorised to have something to do with the electrical charges of the brain. Victims are left with severe swelling around the hippocampus and other parts of the brain that deal with memory, and they are left with no memory of who they are, in a state similar to advanced dementia. 

Gedächtnis Essers sometimes use their ability to steal memories to take over their victims' identities. Due to their unique skills, they also often work in spy organisations and such. It takes considerable effort for them to process these stolen memories. Furthermore, it seems the memories extracted from a Grimm will leave them in a traumatic state, given the violence they often inflict upon Wesen. Consequentially, they are quite fearful of Grimms.

Gedächtnis Essers possess an extremely severe woge. They lose all their hair, their skin turns a fleshy pink with a dark maw, and they grow multiple tentacles. Of these tentacles, they have four main ones which are longer than the rest, and each tentacle is covered in multiple suction cups. These are the four tentacles mentioned above that are used to extract memories from their victims.

Geier:

A Geier (GY-er) is a vulture-like Wesen. Geiers have an innate ability to move through trees and are very adept at ambushing their prey in forest terrain. They attack from above, patiently awaiting their opportunity. They appear to be no stronger than ordinary humans but are certainly much more agile and far faster.

Geier are a communal race, living and working with groups of their own kind. These creatures are harvesters who take pleasure in the pain of others. Geiers gut humans for their organs and blood to use as homeopathic medicines (a substance that causes the symptoms of a disease in healthy people would cure similar symptoms in sick people) and aphrodisiacs (a food, drink, or other thing that stimulates sexual desire) within the Wesen creature community, and they are responsible for obtaining with care such substances for the benefit of Wesen kind. This gruesome practice may be referenced to an actual vulture's role as a scavenger, feeding on the carcasses of people and animals who died in desert areas. Like most Wesen, Geiers are terrified of of Grimms.

Features:

When a Geier woges, the creature's hand elongates and grows sharp talons, which they use for defense or attack. Their feet grow an additional talon on their heel, making attacks from the air more effective. They also develop a hook-like nose, resembling a vulture's beak, and gain dark black eyes. Like a few Wesen, they can localize their woge to their eyes. 

Gelumcaedus:

A Gelumcaedus (GAY-loom-KY-dus) is an alligator-like Wesen. Physically, Gelumcaedus are incredibly powerful, able to tear a man's limbs clean out of their sockets and cause multiple fractures simply by shaking them. Their grip is nearly impossible to escape. They are durable creatures, able to withstand great force. They are also able to move with incredible speed for their large size.

Gelumcaedus are exceptionally hardy and adapted to living perfectly in dark and severely fetid conditions without any noticeable health problems as a result.

Gelumcaedus are commonly known to have dormant periods when they retreat to bunkers fashioned within storm drains and live off of their plunder. One of the oldest known Wesen species, they served in the Praetorian Guard during Caligula's reign and were hired to protect the newly built aqueducts. They carried on in this role throughout Rome's history, and when Rome fell, they retreated into the aqueducts to get away. Some speculate this is why they're fond of storm drains.

Gelumcaedus are an incredibly aggressive and dangerous Wesen that will attack with little provocation, using their powerful jaws and inhuman strength to literally break apart those that get in their way. 

Their relationship with Grimms is one of both fear and respect. They refer to Grimms by their old Latin name, Dēcapitāre, which means "he who decapitates." Grimms use a weapon called a vambrace that is specifically designed to do battle with and kill a Gelumcaedus.

Features:

When they woge, it is quite severe and very different from their human appearance. Gelumcaedus gain thick, pale-green skin. Their mouths extend forward, widen, and become filled with razor-sharp teeth. Their hair and outer ears disappear, and they gain sharp claws.

Vambrace (used by Grimms to kill Gelumcaedus):

A vambrace is a leather arm protector created specifically to battle a Gelumcaedus and features a double-sided, ten-inch, retractable blade. Upon it is a picture of a Gelumcaedus, obviously signifying it's purpose.

Genio Innocuo:

A Genio innocuo (JEE-nee-oh in-NO-koo-oh) is a tortoise-like Wesen. It does not have a commonly used English vernacular (native-themed) name. They are rare Wesen known for being shy and reclusive. Genio innocuo are notoriously intelligent, compassionate, and thoroughly nonviolent. However, their own genius has been known to do them more harm than good in some cases.

A known colony of this Wesen lived on the Galapogos Isles, but many were slaughtered when a Endezeichen Grimm (see chapter 3) slaugtered them even though they were harmless.

Features:

When woged, their skin becomes scaly, their face becomes tortoise-like, and blunt claws sprout from their fingers, which are used, not as offensive weapons, but for digging. It should be noted that while Genio innocuo do not gain shells when they woge, they do gain a shell-like scale pattern on their backs which differs from family to family.

Glühenvolk:

A Glühenvolk (GLOO-in-folk) is an alien-like Wesen. They are extremely rare, humanoid reptilian creatures with magnificent glowing skin, giving them a very extraterrestrial-like appearance in recent times. They appear to be somewhat stronger than humans, and are also fast creatures and posses great stamina.

Theere are two reasons why Glühenvolk are so rare. One, they are hunted for their glowing skin, which is of great value in the Wesen Black Market and sometimes even the Human trade. The second reason is because of the complicated requirements for a female Glühenvolk to give birth. As a pregnancy advances in female Glühenvolk, she needs to consume a greater quantity of cow ovaries to prevent the premature delivery of the child. During the third trimester (about nine months into the pregnancy) , the female is no longer mobile enough to endure the physical nature of the hunt. During this time, the male Glühenvolk will harvest the ovaries for his mate during the night under the cover of darkness.

Glühenvolk are a benevolent species; they do not like to kill accidentally or intentionally. Male Glühenvolk are extremely caring and protective of their mates, especially if their mate is pregnant. Attempting to harm a Glühenvolk's mate is one of the only ways to elicit a violent response from them. When a female Glühenvolk is pregnant and must consume cow ovaries to stay healthy, the mate will gather cow ovaries for her. Due to their disdain for violence, Glühenvolk prefer to attack the cows while they are asleep to lessen the rush of adrenaline.

Glühenvolk are a very ancient Wesen species whose roots can be traced back to Africa. In the past, their magnificent skin was thought to have magical properties, and today, it is simply valued for its beauty. Consequently, they have been hunted to near extinction and are considered as such by most other Wesen. Due to their rarity and beauty, many Wesen consider seeing a Glühenvolk to be good luck. In modern times, sightings of Glühenvolk have led humans to believe in the existence of extraterrestrials, and they are of particular interest to ufologists.

Features:

When they woge, Glühenvolk gain bulbous heads with a barely visible nose and ears. Their mouths are filled with yellow, peg-like fangs. Most notably, Glühenvolk gain reptilian, bio-luminescent skin that glows a gentle, yet brilliant electric blue. The bioluminescence of these creatures is caused by luciferase, a class of enzymes found in many organisms like fireflies and many deep sea fish. Their eyes also turn the same shade of blue but do not glow. A  Glühenvolk infant is born woged. 

^ Glühenvolk Male Woged ^

^ Glühenvolk Female Woged ^