Skrulls

The Skrulls are a race of evil aliens in the Marvel universe.

Origin and Heritage
Millions of years ago, the beings known as Celestials performed genetic experiments on the reptilian ancestors of the Skrulls, resulting in three branches of Skrulls: The Prime, the Deviants and the Eternals. Eventually the three branches warred with one another, and the Deviant branch — due to possessing the innate ability to shapeshift — were triumphant, and afterward wiped out all members of the other two races until only two were left: the Skrull Eternal, Kly'bn, and Prime Skrull of the original non-Deviant Skrull race. Kly'bn implored them to spare his life, as killing him would kill part of their heritage. The Deviants' leader, Sl'gur't, eventually fell in love with Kly'bn, with the two eventually becoming the gods of the Skrull pantheon. As Kly'bn could not change, Sl'gurt vowed to never keep the same shape for too long. Taking the name Prime Skrull, the last original Skrull escaped to Earth in the 20th century and later became a member of the Underground Legion. From that point, the Skrulls began to expand their territory. The Deviant branch later split into two more groups, the modern Skrulls and an anomaly called the Dire Wraiths, a parasitic race that could still shapeshift and had knowledges of magic, but were not as technologically advanced as the Skrulls.

The modern Skrulls originate from the planet of Skrullos, and were originally a mercantile civilization, primarily interested in free trade and willing to share their technology with all races they deemed worthy. When they encountered a new race, they simply transformed themselves to resemble that race. The Skrull empire that resulted from these contacts was based on free trade and mutual cooperation. The empire is controlled by an emperor and each of the 978 worlds is controlled by a governor.

Features
They are green-skinned, with pointed ears and grooved chins. They also possess stereoscopic eyes, opposable thimbs, ruffled chin and very large brains.

History
They are infamous for their ability to shapeshift into any person or creature. With this ability alone they have caused innumerable amounts of chaos and manipulation in the Marvel universe.

The Skrulls were once a peaceful space-faring race of merchants long ago, until then then they met the Kree, a hostile culture of alien warriors. Everything changed since the unfortunate encounter with the Kree, the Skrulls decided to train themselves to combat against their sworn enemies. But now, violence and conquest are the Skrulls' way of life.

The Skrull Empire is hostile to most other species, especially the Kree. During their age-long battle with the Kree, the Skrulls discovered that Earth was a key point in the galaxy in attacking the Kree's home planet, so they were resolved to take over the earth and destroy its inhabitants. They first saw the Fantastic Four as their main threat, so they tried to dispose of them, but failed. Since then, the Skrulls have waged war on almost every hero in the Marvel universe, even launching a mass invasion by impersonating all of the main superhumans on earth.

In one attempt to get rid of the Fantastic Four the Skrulls created the Super-Skrull by taking each of the FF's DNA and putting it into one of their warriors, Kl'rt.