Still accompanied by Nyx, Callum, Rayla, and Azymondias find their way out of the Midnight Desert on the back of their Ambler. After waking the trio, and receiving a couple of angry sparks flung at her by Zym, their new ally tells them that the dragon's lair, the Storm Spire, lays only one day ahead of them. After dismounting the Ambler, Nyx expresses her gratitude for being saved and her remorse for attempting to betray the group. In return, she warns them about the thin air on top of the Storm Spire and calls them even before flying off.
Ezran makes his way to Xadia on Phoe-Phoe's back. After a long night, he offers the loyal Moon Phoenix to rest, but she refuses. When Bait claims that he could need a break, Ezran jokingly asks how he could be tired.
Protected by a group of soldiers, Viren rides out towards Xadia with Kasef, Soren and Claudia. When Soren notices Aaravos's host body, he attempts to squish it, thinking he would do his father a favor, but Viren tells him that he considers the bug an animal familiar, which is quickly dubbed "bug-pal" by his son. Aaravos overhears the conversation and mockingly asks his partner in crime if their relationship had grown to the level of becoming pals, without much response from Viren. When the Archmage sits to rest on his illusionary horse, he wishes to learn how a simple human managed to bring down the Dragon King Avizandum, seeing as he was known as the most powerful creature in the world.
Viren agrees to retell the tale of how Avizandum met his end, which centered on the acquisition of the heart of a Magma Titan, which he describes as something Katolis "desperately needed". He paints Avizandum as a cruel monster when he speaks about the murder of Sarai, their beloved queen. He recalls how many years passed and that King Harrow appeared to have found joy in his life again, as he is seen playing hide and seek with Bait and Ezran. When Viren enters the room, he informs his old friend that an opportunity to get revenge has finally turned up, but Harrow refuses to believe that anyone could harm a godly creature such as the King of the Dragons. Viren reassures him that he has found a weapon mighty enough to slay the dragon and they move to the study. There, he shows him two items: A jar that contains Sarai's final breath and the horn of a unicorn, which he acquired with the help of Claudia. Together they are promised to forge a powerful spell if attached to a weapon, but Harrow remains unsure if revenge is the right approach, knowing that times are peaceful. The pain still strikes him deep however and sadness turns into anger, causing him to allow Viren to cast his dark magic onto Sarai's spear.
Back in the present, Soren introduces himself to Kasef and notices his accent. Although he guesses his home country right, he fails to pronounce Neolandia correctly, despite Kasef's corrections.
Once Phoe-Phoe enters Xadia, Ezran can not contain his excitement, but quickly notices that his friend has become gradually more exhausted, hardly able to keep her eyes open. When she lands, she collapses to the ground, panting heavily. Ezran urges her to rest once again, but Phoe-Phoe insists to finish the journey, promising she will be alright.
Kasef feels weirded out by Soren and moves on to ride next to Claudia instead, mentioning that he thinks her brother is somewhat quirky. Claudia is surprised, stating that people usually refer to her as the quirky sibling. Kasef then notices that Viren is seemingly talking to himself, but Soren reassures him that it is just his "bug-pal" he is talking to, which does not make anything less disturbing to Kasef.
The scene switches back to the past, where King Harrow and Viren scan The Border for Avizandum, but find him missing at his watchpoint. They travel to the Storm Spire, where the mighty king descends from the sky to face his enemies. The dragon claims that it is a special day on which he will spare the lives of the humans. However, they do not accept his ultimatum to leave or die, and instead immobilize their opponent with Viren's staff, followed by the enchanted spear. The weapon penetrates Avizandum's chest, where the magic begins to petrify him, spreading over his wings. The dragon attempts to escape but succumbs to the rapidly growing stone curse. He sheds a last tear as the stone engulfs his entire body. Instead of leaving, Viren hesitates as he realizes that the reason for Avizandum's absence had been the birth of his offspring. Deeming it a danger, due to the risk of a future retaliation from a vengeful Dragon Prince whose goal would be humanity's annihilation, he convinces Harrow to ride to the lair to destroy the egg. As he rides by, he passes the stone figure of the king of dragons. When the time changes back to the present, Callum and Zym gaze upon it, to the unease of the baby dragon.
Aaravos is delighted about the outcome of the story and tells him that Avizandum is the reason why he has been imprisoned for centuries, though he doesn't know where his prison resides. Viren believes the prison to be rather odd, but the Star elf guarantees him that it is anything but pleasant. Suddenly Kasef interrupts the two, informing Viren that the Breach has been destroyed. The group believes their only way to be blocked, but Claudia reveals the horn of Pyrrah, which can be used to cross with the help of dark magic.
Phoe-Phoe finally descends, reuniting Ezran with his brother and friends, who are sharing a warm welcome. However, the phoenix finally succumbs to exhaustion and sickness and collapses once more, taking her last breath after Ezran praises her for her determination to bring him to Xadia. When Ezran realizes that she has died, tears form in his eyes as Callum pulls him into a comforting embrace. Suddenly, Phoe-Phoe's body incinerates in blue flames, leaving behind a single feather. Ezran is reminded of a Moon Phoenix's ability to resurrect, knowing Phoe-Phoe will one day be with them again.
Upon reaching the Breach, Viren casts a dark magic spell by using the horn which causes the lava to part in the middle, forming a pathway for Viren's army to cross.
Gazing at the petrified body of the dragon, Callum expresses his hatred for Avizandum based on the fact that he has taken the life of his mother. However, he is not sure how to feel, seeing as he should be glad to have gotten revenge for Sarai's death, or feel sadness and regret since Avizandum was Zym's father. Rayla promises him that together they will break the cycle of hatred, vengeance, and violence between the nations.
- The process of enchanting Sarai's weapon was foreshadowed in the credits of "Heart of a Titan", where Sarai's spear, the jar containing her dying breath, and the unicorn horn were shown.
- The scene where Viren parts the stream of lava resembles a scene in the bible, where Moses parts the sea to let his people cross after being given this power by God himself.
- Viren taking the egg and trying to destroy it out fear shares a resemblance to the Fire Nation's actions in trying to kill Aang out of fear in the "Avatar: The Last Airbender" series.
- Nyx's warning foreshadows the warning sign Team Zym comes across in "Hearts of Cinder".
- The picture of Team Zym with the Storm Spire behind them foreshadows their climb in "Hearts of Cinder".
|Team Zym||Callum • Ezran • Rayla • Bait • Azymondias|
|Humans||Callum • Ezran • Harrow • Viren • Claudia • Soren • Amaya • Gren • Corvus • Ellis • Sarai • Opeli • Aanya • Annika and Neha • Florian • Fareeda • Ahling • Villads • Kasef • Saleer • Crow Master • Barius • Allen • Marcos • Fen • Ziard • The Orphan Queen|
|Elves||Rayla • Runaan • Lujanne • Janai • Aaravos • Nyx • Ibis • Ethari • Kazi • Khessa • Tiadrin and Lain • Aditi • Moonshadow Elf Assassins|
|Dragons||Azymondias • Avizandum • Zubeia • Sol Regem • Luna Tenebris • Pyrrah • Rex Igneous|
|Minor Characters||Delilah Giehl • Doctor • Hendyr • Lissa • Sabah • Sir Phineas Kirst • Sunfire High Priest • Terry • Tristan|
|Animals||Bait • Phoe-Phoe • Ava • Pip • Berto|