It remains unknown if the entities know as the Creators were one species or an interestellar association of different species but were most probably humanoid as they created the Guyver Units which they used during their visit on Earth. They are believed to have manipulated life on Earth over millions of years to create a biological weapon which resulted in the creation of humans. With whom they were at war remains a mystery. Their technology is believed to have been advenced enough to enable them to move planets across galactic distances.They seem to have disappeared but left their creations behind.
Source : Guyver universe