I don't have a lot of stuff solidified for this alien yet, but I know they have some form of shapeshifting ability.
They take in cells of other beings either through consumption or through scientific injection in order to change into something else.
They also come from a planet where these huge mushrooms have dominated the entire world, so every living creature on the planet relies on the spores of these mushrooms in order to survive.
You may not use this work for any purposes.