As the enforcers and team 5ds clear out the city they are met with the former gang members the enforcers defeated. taken over by the darkness in their hearts. they scorn the enforcers for their defeat wishing they pay for the pain they caused them before back in the day.

Yusei calls out to one of the gang leaders " I know what we did back then is wrong but now we make up for it , We do not have to fight "
" no the past is gone now we will make you feel the pain we faced "
They all arm their duel disk and focused on one word duel

Yusei will attempt to save one of the members while , Jack , Crow and Kalin is forced to defeat their opponent for they had fallen too far into darkness.

As dawn's light slowly enters the world their time runs short. they must hurry so they rush to the ener-d reactor deep underground. Team 5ds then use their D-Wheel to channel their energy into the reactor. as they did a gate opens , the door to the spirit world.

It will be multi tiered inside the spirit world leading to the final battle

Yusei feels anxious as the final battle draws near he wants to save him but can he do it alone. " Can I really fight my own father "
His brothers console him " you know it must be done . But you are not alone you will have us "
" Yeah all of us "

This battle will be 3 on one . Dr fudo uses the earthbound Inca deck Goodwin has but with all earthbounds. Yusei will defeat him with Cosmic Blazar Dragon or Shooting Quasar Dragon.

If the Nordic gods are present Dr. fudo is revived. if kalin is present he will go to the afterlife. If Dr fudo is revived he will pass out upon going back to the human world and taken to hospital.

- This brief time is all we get
- Don't cry my son even if I am gone I will always be inside you but you are not alone you will be with your brothers.
Dr fudo then fades away as yusei calls out his name before being brought back to the human world.

Yusei falls to the ground with tears on his eyes " I cannot save him "
Depending on how well you know 5ds lore it's basically good ending . bad ending.

This related to the darkness in yusei' s heart how you read it is up to you. Basically yusei will or likely cause the zero reverse again.