The ultimate symbol for the Ruler of the Universe is the golden mecha.
This is the case for both Five Star Stories and L-Gaim.
In LGaim, The Original Auge was linked with the soul of it’s pilots, as well as shared between the couple Mian Attsher and Olnda Poseidal (Amandara Kamandara).
In FSS, The Knight of Gold was made as a symbol of the union between Lachesis and Emperor Amaterasu (Ladio Sopp). Also because Lachesis was a fatima, she co-pilot the machine with her husband.