|Powers and Abilities||Shapeshifting|
Over the course of history, they developed the ability to shapeshift into anything or anyone they want. They also fought the Kree for centuries.
The Skrull homeworld, Skrullos, was destroyed by Galactus. This was happened as a prophecy foretold it would. A second foretold that the Skrulls would claim a strategic location known locally as Earth.
As the Kree also set their eyes on Earth. They began infiltrating every human organization and groups on the planet, taking out and replacing each targeted member with no warning.
It is unknown if they could be detected by human technology or instincts, but it was proven that Doctor Doom's advanced technology can detect a Skrull in disguise as he found out that Invisible Woman was indeed a Skrull posing as the real one.
Their invasion was stopped by the forces of Earth.
For the Skrull Empire military are a handful of Skrulls that are genetically enchanced with the powers of several superpowered and technical advanced people from Earth. The first Super-Skrull was Kl'rt, the rest were on the secret invasion mission, but they were all eventually captured and send to the super Prison 42.
Powers and Abilities
The Skrulls can shapeshift into any human or any superhero and supervillain as well in their infiltration on Earth to pave way for their invasion. They can also mimic their voice as well to prevent suspicion from other individuals.
Skrulls are shown to have enhanced speed, strength and durability, which is why Captain America was one of the easiest to replace since his powers are similar to them.
It is unknown how they duplicate a person's powers and abilities if a Skrull doesn't naturally have them, possibly using mutation or technology, such as Invisible Woman's shielding abilities and invisibility.
They also have very advanced alien technology and weaponry almost equal to the Kree in their war for centuries.
Despite their morphing ability, they can still be seen using Earth and other alien technologies. Also if knocked out some or all Skrulls may revert fully or half way from their disguised forms. They can also slip out that they're imposters for reasons such as: actions, personality and memories since a question or something else may be based on the person's past.