The Mycenaean were an ancient people from the Mazinger Z series who made giant robots and had super tech long ago. Their tech was rediscovered by Dr. Hell, and Juzo Kabuto who used it for different reasons. In Shin Mazinger Shougeki! Z Hen its implied they were aliens or something.
Mazinkaiser Manga[]
In the 2003 Mazinkaiser Manga by Go Nagai and Naoto Tsushima, Koji Kabuto goes into space on a ship to a big a55 satellite that don't reflect waves so its undetectable from da urth. Its been there thousands of years and was pat of the Mycenaeans that were really aliens who the early humans worshipped as gods like f--king ancient aliens! Anti Ashura sez the tech from Mechanical Beasts and Mazinger is from there and she/he takes Koji to meet... His Grandpa Juzo Kabuto!! Turns out the Juzo who bad Ashura killed was a clone and Real Juzo made 2 clones of himself to help him and 1 turned evil and became Dr. Hell (Good f--k! Thats a pretty f'd Retcon! What next?! Optimus and Megatron being Brothers?!). Real Juzo (Shin Juzo??) sez theres good and evil in us all and Koji chose to be good unlike evil clone Juzo. But then the evil Juzo launches an all out attack like in Mazinger Z Infinity and Mazinkaiser OVA 1 to slag Great Mazinger and Shin Juzo Kabuto gives Koji Mazinkaiser to stop his evil clone.