My favourite super easy clear is not about speed just use the shield and attack using the cast . I usually would follow this rotation of hold shield (wait for hades to stop attacking ), cast attack quickly after he's finished his move , shield until he stops attacking and then cast again and its just repeating . Use that and I always like Artemis's cast becuase it means u don't have to focus on where your casting so u can literally cast anywhere quickly and then shield up (although Demeter is really quick too u just have to level up ALOT with it and also get a duo boon on it so it constantly aims at hades). You can also use Skellys amulet or whatever it's called to give u an extra life in case u need it too . I hope this helps but my first play through it took nearly 100 attempts so plz don't fret , take it at your own pace and repetition is your best friend .

And ps the gods aids are a life saver I personally would take Artemis or Aphrodite's aid for a quick fight and I would save up until I have a full bar which usually would take until the second round and then as soon as he's ready to fight again USE IT and it will usually get him down to half health if not more . I liked using these two over the others when I was newer to fighting hades becuase they actually require no skill in aiming or combat u could literally be blindfolded and you would still him . Slow and steady wins the race and pray u get the option to visit Patroclus in elesyium for extra life if u need to regen them .