Homebrew Changeling (Star Trek) Species Details

"They're goo-people. Walking, talking clay-dough. They can replicate a person on sight alone. Voice, mannerisms, s-speech patterns, but that's it. You... Most of the time, you can tell. Ask him a question they should know the answer to. Simple question, wrong answer-- boom, Changeling."

– Liam Shaw

Morphogenic Matrix

Changeling's body is not made out of cells, but of a biomolecular structure known as their morphogenic matrix. The lack of cells means that Changelings are not affected by senescence, being biologically immortal as a result. They have no sense of smelling and their minds cannot be read even by naturally telepathic species. It appears that when a Changeling assumes a specific form, it does not only mimic its external appearance, but its molecular structure as well. When they become rocks, for example, a sensor will not detect them as lifeforms. This doesn't make them vulnerable, however, since they can immediately return to their liquid state at anytime.

Changelings do not eat or drink, and need no air or any other substance to live. Since they need no sunlight either (their adopted homeworld has no sun), it is a complete mystery how they get the energy they need for living.

Founding of the Dominion

Changelings are an ancient race believed to have originated somewhere in the Gamma Quadrant. Once peaceful explorers, they suffered prejudice from several "solid" races, who were afraid of the Changelings' almost unbelievable powers and resilience. The Changelings finally decided that the best way to protect themselves was to take control of their surroundings, and thus they founded the Dominion, a major military organization that rules most of the Gamma Quadrant. The Changelings (or Founders, as they are usually referred to) are the absolute rulers of the Dominion, but are still very reclusive and enigmatic, being treated as god-like mystical entities by their servant races. The warriors of the Dominion are Jem'Hadars, a violent humanoid species genetically created by the Founders.

The Great Link

Most Changelings have little sense of individualism. They enjoy merging themselves together to become part of what they call the Great Link, a gigantic ocean of Changelings in their natural liquid form, all deeply interconnected on a physical and mental level. Changelings are so isolated that some species in the Gamma Quadrant regard them as just a myth, being unaware that they're the real force behind the Dominion.

Changeling Names

Most Changelings do not have given names, and instead take on the name of the entity they are impersonating. However, some Changelings who have disagreed with the Dominion's notion that humanoid life should be enslaved to restore order in the universe have given themselves their own names. 

Male Changeling Names: Auron, Indurane, Laas, Odo, Selann

Female Changeling Names: Vadic

Changeling (Star Trek) Traits

As an ancient and amorphous race, you have many strengths that come with being a Changeling.

Language

As a Changeling, you can understand and speak Common as well as whatever language of the form you are currently inhabiting. 

Speed

Your base walking speed is 30 feet.

Thick Skull

As a Changeling, you are highly resistant to telepathic abilities like mind reading and mind melds. You have advantage on Wisdom Saving throws. 

Ability Score Increase

As an ancient being who has trained to blend into your surroundings, your Constitution and Charisma increase by 2.  

Age

Due to your body not being made out of normal biological material, you are essentially immortal. This does not mean you are invincible, however. 

Alignment

Changelings that are a part of the Dominion usually have very xenophobic views against other lifeforms, believing themselves to be superior. They will use their abilities to manipulate others and to insert themselves into places of power in other races' governments. Changelings that are part of the Dominion will fall under the Lawful Evil or even Chaotic Evil alignment. Changelings that disagree with the Dominion usually are Lawful Good to True Neutral. 

Changeling Instincts

As a Changeling, your ability to blend into your surroundings gives you proficiency in Deception, Stealth, and Survival skills.

Changeling Disguise

As an action, you can transform your appearance or revert to your form that you usually assume. You can’t duplicate the appearance of a creature you’ve never seen, and you revert to a golden gelatinous liquid if you die. You decide what you look like, including your height, weight, facial features, the sound of your voice, coloration, hair length, sex, and any other distinguishing characteristics. You can make yourself appear as a member of another race, though none of your game statistics change. Your clothing and other equipment don’t change in appearance, size, or shape to match your new form, requiring you to keep a few extra outfits on hand to make the most compelling disguise possible.

If you decide to assume the form of an inanimate object, you can no longer move until you revert back to an animate form. You will still have all of your game statistics and take damage the same as otherwise. 

Even to the most astute observers, your ruse is usually indiscernible. If you rouse suspicion, or if a wary creature suspects something is amiss, you have advantage on any Charisma (Deception) check you make to avoid detection.

Size

Changelings have the ability to transform their morphogenic matrix into whatever object or being they see fit. However, your normal height and regular form you choose to look like will be under the medium category.