Aberration

An Aberration is "any person who has undergone a process [involving magic] turning themselves into parasitic monsters, physically and mentally, in an effort to unnaturally extend their own lives". There are multiple types of aberration.

General rules

Aberrations vary greatly in form, abilities, and method of being all spooky and parasitic, but they all have the following things in common:

• Used to be human and chose to become aberrations
• Parasitic existence feeding on humans to lengthen lifespan
• Monstrous form, either all the time or just when using powers
• A complete lack of empathy for other living beings
• No known way to return to being a regular human
• Universally difficult to harm with physical attack, but weak against magic weapons

Detection of vampire hunters

The magic weapons weakness makes people with talent to summon magic weapons - like Susan or Diane - natural vampire hunters. There is no "default" method for detecting such ability, but vampires are trying to find some and most succeed. Usually it's to avoid them - while both Susan and Diane was attacked before awakening, most vampires are not able to distinguish that and avoid all people with such talent even if not awakened.

Types of aberrations

So far every aberration we saw was unique, but presumably they tend to follow similar patterns, if only because of common inspiration.

Vampire-like

Vampire-like Aberration

The first type of aberration seen in canon was a vampire-like aberration. It hypnotizes young women and sucks blood out of their necks. It can recover from almost any wound not caused by a magical weapon, and can sense people with the potential to cause it harm. It is unknown if the non-vampiric traits are shared with all aberrations, or just vampire-like ones. Other than the vampiric traits described above, this type of aberration shares few, if any, other traits associated with vampires. For example, traits it does not possess include: an aversion to garlic, sensitivity to sunlight, the ability to turn people into vampires, and an aversion to holy symbols. In addition, neither this type nor any other type of aberration is considered undead, as the undead do not exist in the EGS multiverse; this information is irrefutable, as it was given by Dan. The only known aberration of this type was the aberration that attacked Susan and Nanase in France, and it was subsequently killed by Susan with help from Nanase and the French Immortals.

Spider-like

The spider (or spiderman)-like aberration looks close to the vampire one, but seems to not use hypnosis. The fact it detected Diane as "potential vampire slayer" suggest that similarly to vampire it's vulnerable by magical weapons. He also identifies himself as vampire.

Body snatcher

Body Snatcher Aberration

The second type of aberration seen in canon was a body snatcher aberration. This type possesses a human host and controls its host's body entirely. A body snatcher is considered the worst kind of aberration by immortals. It can continue possessing its current host's body even after its host becomes brain-dead, but it cannot begin to possess an already brain-dead host, even if it possessed it previously. It can communicate with beings on the spiritual plane independently from its host. Beings on the physical plane see only its host, not the aberration itself. It can change hosts at will. The only known aberration of this type is Sirleck.

Big mouth one

Another type of aberration looks like having another mouth in belly and eyes above that, and eats people whole. His original head can still be used for camouflage, though.

Fluffy

Another type of aberration looks like fluffy/furry animal hybrid. These include the fluffy snake wearing Dracula cape and the Koala one, who previously appeared in human form as kangaroo charity person although we quickly got reason to suspect he's aberration.

Looking at their teeth, they likely eat whole people like the big mouth one, although not in one piece.

Both of them, along with the big mouth one and the next unknown one, are likely part of six Sirleck hired to attack Adrian Raven.

Unknown

The other guy talking with big mouth aberration is also aberration, but we don't know what type.