The plot involves the coming of Lucifer to the Sanctuary, where his underlings systematically dispose of the surviving Gold Saints. Athena goes to Lucifer to ask for peace, placing herself in peril. The Bronze Saints must then come to her rescue, destroying Lucifer's Fallen Angels (Seima Tenshi in Japanese) in the process.
Saint Seiya: Warriors of the Final Holy Battle streaming: where to watch online?
Currently you are able to watch "Saint Seiya: Warriors of the Final Holy Battle" streaming on Pluto TV, Retrocrush for free with ads.