Skrulls

"You are just one victim of the Skrull Expansion that has threatened our civilization for centuries. Impostors who silently infiltrate, then take over our planets."

- Supreme Intelligence to Carol Danvers

The Skrulls are a technologically advanced race of reptilian humanoids that possess shapeshifting abilities. They had their home planet destroyed by the Kree.

Kree-Skrull War
The Skrulls lived on their home planet Skrullos. However, their expansionist beliefs led to conflict with the Kree who defeated them in a genocidal war and destroyed their homeworld. The thousands of Skrull survivors used deception and their shapeshifting abilities to seek refuge in various planets by blending in with their population. The Kree Empire began a propaganda campaign that depicted the Skrulls as evil invaders who infiltrate planets with the intention to conquer them in order to hunt down any Skrull refugees they could find.

One faction of the Skrulls led by General Talos found temporary refuge aboard a Kree cruiser hidden in Earth's orbit, being sheltered by the renegade Kree scientist Mar-Vell, who researched a way to build a Light-Speed Engine, hoping to provide transport to the faction away from the Kree's war. However, Mar-Vell was assassinated before she could complete her work, resulting in the refugees residing in her spaceship for six years.

In the 1990s, several Skrulls were killed by Starforce during the Ambush on Torfa. Talos kidnapped Vers and tried to read her mind with a memory probe. Vers escaped, killing several Skrulls and causing her and the surviving Skrulls to land on Planet C-53. The Skrulls took human forms so they could find the Light-Speed Engine in the hopes of finding a new homeworld beyond the Kree's reach.

Eventually, Talos and Norex formed an alliance with Vers and Nick Fury once it became clear that the Skrulls were, in fact, victims of the Kree. In the fight in Mar-Vell's Laboratory Vers, Fury and the Skrull warriors recovered many Skrull refugees and civilians, including Talos's wife and daughter, whom Mar-Vell had helped hide. After defeating Ronan the Accuser's fleet, Captain Marvel decided to help the Skrulls find a new homeworld and look for Skrull survivors scattered throughout the galaxy.

Skrull Detectors
The Skrulls were known for their shapeshifting abilities, making them difficult to recognize if they were working undercover. That led to the development of Skrull detector technology. In 2013, one black market trader on Conjunction was selling Skrull detectors for ten units apiece.

Characteristic Traits
The Skrulls are a humanoid species with distinguishing features that include green skin and pointed-back ears. Unlike many species that are native to Earth, Skrulls are not carbon-based lifeforms, and are apparently based on an element not on the periodic table.

They are also able to shapeshift into other beings, right down to the individual's DNA. They are all physiologically capable of this, but accurate shapeshifting requires practice and talent. Also, they are able to replicate the recent memories of the person that they are copying.

Notable Skrulls

 * Soren
 * Talos' Daughter

Trivia

 * In the comics, the Skrulls are a race of alien shapeshifters bent on invading Earth as an advantage in their prolonged war with the Kree. The Skrulls managed to replace many of Earth's heroes with Skrull operatives in what was called the Secret Invasion.
 * In the Agents of S.H.I.E.L.D. episode Eye-Spy, the Skrull alphabet from the comics appeared along the Words of Creation on a chalkboard in Todorov Building.
 * In Guardians of the Galaxy and Guardians of the Galaxy Vol. 2, the Skrull alphabet from the comics is used on various computer screens.

Behind the Scenes

 * The film rights to the Skrulls are co-owned by and Marvel Studios, similar to the rights of the Watchers, Quicksilver, and Scarlet Witch. However, certain Skrulls and Watchers characters were owned completely by Fox such as Kl'rt the original Super-Skrull and Uatu.
 * The Skrulls were believed to be featured in The Avengers as Loki's army, however, Joss Whedon debunked this, saying that "The Skrulls — they can shape change. That's a whole thing. I've already got Loki. He's got magic. Once you got magic along with your Iron Man and your Black Widow — it's a real juggling act." Despite this, the Skrulls were featured in some of the films' toy line merchandise.
 * James Gunn considered implementing the Skrulls in one of the Guardians of the Galaxy movies, but it did not work out.
 * Kevin Feige stated that: "the Skrulls are as diverse and as multilayered as any other intelligent life form. Certainly like humanity itself. And we happen to see good ones. I think there are probably better ones out there as well, like there are with any fully realized characters. But yes, the idea certainly was to subvert the expectation of the pointy-eared green aliens. And Ben Mendelsohn, even subverting people’s assumption that Ben Mendelsohn will be playing the villain."