Fan Casting The Black Knight in Shining Knight

Is Vandal Savage in disguise however I wouldn't have it revealed until the end after he has been driven out by the newly super powered Shining Knight. Maybe already has the God killer sword? Was thinking that maybe Excalibur could be like a counter to the God killer sword and this becomes important later? Maybe Superman fights Savage with Excalibur in The Savage Time? Also prompts his conflict with Justin (Ok so maybe Superman doesn't literally swordfight Savage, maybe he could if that's what would sounds cool but maybe instead Justin siphons the magic into Superman from Excalibur I.e it's unbreakable qualities? Qualities which restores Superman's invulnerability slightly?)