This is working idea I am putting together for an alien race in the Savage Reich Star universe – one part gray, one part reptilian. They have visited our planet before, realized we were not ready for contact and left us alone. Unfortunately, one of their patrols crashed in 1937 – leading to the die Glocke Project.
The Aliens call themselves the Vrokkix or simply the Vrok. They are a reptilian version of the classic gray aliens of folklore. They are tell (about 8 ft), gaunt and scaled. They are unusually strong. Some have strong psychic abilities. They also mastered the secret of immortality.
They have advanced technology that exceeds anything that is on Erde – FTL flight, teleportation, advanced AI tech, nano-tech and bio-tech.