The first to go was Pleione. Not many in the mortal world remembered her, so it was no surprise when she flickered out of existence. 

Next to go was Hesperis, mother of the Hesperides. As she faded, she traversed through the world, trying to get to the Garden of the Hesperides. She never made it, fading right outside the gates, not being able to hug her daughters one last time.

Apollo watched all of this, unable to look away as he watched his fellow immortals disappear. 

Aegle was the last of the Hesperides, the pain of seeing their mother and their sister die without being able to say good bye one last time was too much for them. As Aegle faded she spoke softly to the sky, saying, "Good bye Zoë, may you find ever lasting peace in the stars."

Calypso traversed the world with Leo, and when she heard the news about her sisters fading, she faded as well, causing Leo to burst into tears, unable to hold in his pain anymore. He didn't live much long after.

Zagreus, god of rebirth disappeared into the wind, without a single word. Melinoe, consumed with grief followed her brother quickly, taking all the spirits with her.

Eumolpus, the ever sweet singing son of Khione sung a somber melody as his mother, his aunt Cleopatra, and his two uncles faded into a small pile of snow.

Apollo cried tears of gold for his cousins, unable to do anything.

Next was Asclepius, god of healing. Few mortals even remembered his name, as none remembered his symbol either. He faded when he was unable to heal Piper McLean of her fractured mind and bleeding wounds. As he left, nectar and ambrosia lost its healing qualities...

Hades, Macaria, and Thanatos were next. They were never really thought of, and as time went on, they were forgotten by mortals, however, due to being chthonic deities, they saw their time coming, and faded while walking out of the underworld, with Thanatos walking hand in hand with his wife, while Hades walked out behind them. Soon after, the Underworld collapsed, with Persephone and other chthonic deities barely surviving. 

As Nico faded, he remembered his promise to Will, how they would never be separated. He chuckled dryly as he slipped into the Void.

Hazel cried out as she and Frank kissed, she felt something was wrong, and she soon found out what it was. She was fading, quickly. She tried to speak, however, she found she couldn't as she had completely faded, and was then in the Void.

Hephaestus was next, as no one really invented or created things in a forge any more. When his beard no longer burst into flame, his children around the world faded as well, some in the process of battling, others sleeping, and others training. They all left the world and went to the Void.

Hera was next. Despite being a bit of a pompous brat, she truly cared for, and loved her family, so it tore her apart when her favorite daughter, Hebe, faded. She coughed up ichor in the middle of the throne room, flickering as she left and joined her children. 

Hestia and Poseidon with his wife and godly children, Triton, Benthesikyme, and Rhodes, left the world, huddled around the godly hearth in Olympus. 

Percy, hugging his girlfriend as he saw his friends die, started coughing. At first it wasn't too bad, but then it crashed down powerfully, expelling blood from his lungs. As he passed on his final words were a grim farewell to his closest friends, allies, and to the huntress in the sky.

Thalia was unable to control her grief at being the last of her cousins and siblings alive, and went on a killing spree, sending all sorts of monsters into the pit until she saw the Minotaur. Her cousins sworn enemy looked at her sadly as it faded, its relationship to Poseidon killing it. She ended its life quickly, making sure to make it painless. 

Dionysus passed on quickly, taking all the booze in the world with him, stopping the Olympians from being able to drink their problems away.

Athena left soon after Dionysus, as wise were rare in the world. Annabeth smiled, glad that she would be able to see her Seaweed Brain again.

Artemis crashed her moon chariot. She was gone before it landed.

Demeter walked among the fields of grain before stumbling and falling, fading before she hit the ground.

Ares, ever violent, left Olympus one Tuesday to go searching for a battle. Within the hour his throne was gone, bringing the world into a chaotic peace.

Aphrodite, goddess of love, tried flirting with one of the remaining gods to lift their spirits and usher in a new generation of gods to watch over the world. Instead, as she spoke, she turned into a waft of fancy perfume.

Hermes, always the hard worker continued to deliver things as the gods disappeared, but as they became the last 3 deities, he faded, with nothing else to do.

Zeus, the king, passed on all his duties to Apollo, and forcibly faded to join the rest of his family, darkening the sky.

Apollo, god of knowledge and prophecies foresaw this coming.He knew what would happen and so he did what he foresaw.

 He fell, and the light of the Sun faded away.