Symbionts

Symbionts were created by the daelkyr thousands of years ago, though it is unknown whether or not the symbionts were created on their home plane of Xoriat or on Eberron after the daelkyr invasion. Regardless, for thousands of years, symbionts have been symbols for the daelkyr, and are often gifts given to worshipers of the daelkyr and the Cults of the Dragon Below. They are sentient beings that are designed to attach themselves to hosts, and act as weapons and armor for their hosts. Since the end of the Daelkyr War thousands of years ago, symbionts still remain scattered across Eberron.
A symbiont can exist on its own for a length of time; however, it will seek a host as soon as one becomes available. When a symbiont bonds with a host, the symbiont immediately tries to take possession of the host, enforcing its will onto the host. Only those with strong wills can overcome the mental invasion of the symbiont. Once the symbiont is subdued the first time, the symbiont will usually act cowed, subjecting itself to the users wishes. However, the symbiont may try to take over its hosts mind again if the host is especially weakened, or if the host tries to do something not in the best interest of the symbiont, like remove it or attack another symbiont. When the symbiont gains dominance, the symbiont is in full control of the host's actions, though it usually becomes apparent that the host is no longer in control of his or her body. Even in a cowed state, the symbiont may subtly influence its host, fanning the fires of rage or increasing a host's hunger for its own nourishment. Some hosts can be driven mad by the constant whispering of a symbiont in its mind.
There are several kinds of symbionts documented in the library in the Citadel of the Closed Circle.

Breed Leech

Breed leeches are eyeless black slugs with lamprey-like mouths. When attached to a pregnant humanoid, the breed leech will inject genetic material into the host, transforming the unborn child into a daelkyr half-blood. The breed leech is usually attached via its mouth to the torso or arm of the host, making sure to be unseen beneath its host's clothing.

Crawling Gauntlet

At first glance, a crawling gauntlet looks like a detached, crawling hand. The hand is actually a chitinous gauntlet, designed for a humanoid hand, and covers up to the forearm. The crawling gauntlet will bond with a host by surrounding the host's hand and embedding itself to the host using tiny tendrils that burrow beneath the skin.

Earworm

This small shriveled worm looks perfectly suited to curl around a person's ear. When it does so, it burrows into the head and bonds to the skull. Once bonded, the earworm allows it's host to understand the speech of Xoriat, and will sometimes share with it's host the thoughts of those around it. When threatened, it can release a psionic signal that induces an intense feeling of fear.

Kyrzin's Ooze

This opalescent, symbiotic goo comes sealed in a jar and slowly shifts and moves, as if endlessly exploring the jar's interior. Kyrzin created many kinds of parasitic ooze, which when ingested confer ooze-like properties on the host, including a resistance to poison and acid damage, and even an acidic breathe weapon. These parasitic oozes have also been known to eat their way out of a host if it displeases them.

Living Armour

Living armour is formed of plates of hard, black chitin, with red veins and sinew pulsing beneath. The user must actually don the armor, at which point tendrils from the armor begin burrowing into the skin of the user. Once bonded, the living armour, like most symbionts, can then communicate with its host telepathically.

Living Gloves

These symbiotic gloves—made of thin chitin and sinew—pulse with a life of their own. They carry knowledge of skills, and can autonomously perform these tasks using the hands of the host. They have been known to pick locks, and use artisan's tools to create wonders.

Shadow Sibling

A shadow sibling is the symbiotic sentient shadow of a creature. The shadow sibling looks like a faint, shadowy humanoid, with indistinct features. When pulled close to the host, the shadow sibling also blurs the features of its host. When the host is enshrouded, the host is concealed and blocked by ambient light. The shadow sibling can also attack others, and its touch can damage the flesh of an opponent while bonded to a host.

Spellwurm

A spellwurm is a thick, purple, snake-like creature about the size of a human arm. The spellwurm has a five-fingered maw, which it uses to attach to hosts. The spellwurm can attach to a humanoid's missing arm, or attach to a humanoid's armpit to act as a third appendage. During combat, the spellwurm will gesticulate, casting spells at the host's opponent.

Stormstalk

The stormstalk is one of the eyestalk of a beholder. This eyestalk is a symbiont, and can bond with a willing or helpless host. When it finds a host, the stormstalk burrows roots into the head of the host, connecting directly to the host's brainstem and bloodstream. At the host's command, the stormstalk can shoot bolts of lightning at other creatures. Unlike other symbionts which are depowered when not bonded, the stormstalk can also emit this lightning blast when detached from a host as well.

Tentacle Whip

This long symbiotic whip can graft itself to the arm of a host. The whip resembles a long strand of muscle that ends in a stinger which is razor sharp and can inject poison into its foes. The tentacle whip requires sustenance, and will drain the energies of its host, though this drain is relatively minimal. The whip is usually 15 feet long, and is also able to channel melee touch spells through it.

Tongueworm

At first glance, the tongueworm appears to be a small cobra with the same color as a human tongue. The tongueworm can enter the mouths of potential hosts, then bond itself to the back of the host's throat and hide under their tongue. The tongueworm can then spring from its location hidden on the tongue of the user, launching itself out of the user's mouth and attack a creature using a poisonous barb. This poison is designed to paralyze its prey, and the tongueworm conveys an immunity to its own poison to its host.

Wandering Eye

This disturbing daelkyr-made symbiont is a leathery tentacle with one end terminating in a single bulbous eye, and the other sporting a barb designed to burrow into flesh. It burrows into the shoulder, and then rises up above the host's shoulder and observes the world around it, projecting insights into the hosts mind.