Big Dover

Most likely related to their mysterious other-worldly nature, or the effects that being in our reality/dimension has done to their form, Dover has the ability to shape-shift. 

This is mostly in the form of changing the size and proportion of their body but can be extended to more minute and precise changes. They’re always them though (They couldn't morph to turn into a copy of someone else to fool you, they’d still be the creepy/cute looking rabbit thing). On top of this they can become scarily invulnerable and dropping a tanker on them would only result in bruises or small cuts. 

There’s a reason why they’re Dr. Lancaster’s personal bodyguard.