Reveal the secret of Yggdrasil

Reveal the secret of Yggdrasil is the second episode of Saint Seiya: Soul of Gold.

Overview
With Aioria weakened after facing Fróði, Lyfia seeks out in search of help and comes across Mu. They discover that sinister plans have overcome a small village and do what they can to save the people before it's too late.

Plot
Helping a weakened Aioria walk, Lyfia learns that there are other Gold Saints besides Aioria. When his brother spoke to him, Aioria became certain that the other Gold Saints have also been revived and must be in Asgard as well. As the two come to an abandon cabin, Aioria collapses from exhaustion. Lyfia becomes concerned about his wellbeing but sees that the cabin does not have any supplies available. Although she does not wish to leave him alone, Lyfia decides she must head out to find supplies.

She makes her way to a small town and goes door to door asking for food and water. With no one seemingly in any of the houses, Lyfia soon becomes overwhelmed with her own exhaustion and collapses. After some time, she awakens inside a barn with only a young boy present. After remembering why she was out, Lyfia meets Aries Mū. After he had saved her when she had fainted, he states that she had been muttering Aioria's name in her sleep. Lyfia admits that he's someone very dear to her and that she had been out looking for supplies to help him recover but wasn't able to find anyone in the town. Mu confesses that he had come across the same situation when he had arrived to the town a few days prior and only found the young boy present.

Lyfia suddenly feels an ominous presence and the group notice a pair of Asgardian soldiers searching the area. The young boy states that the soldiers make patrols every day and Mu has described seeing someone wearing a dragon cloth. Lyfia figures that is must be Níðhöggr Fafner; a God Warrior under the command of Andreas Lise who enjoys human experimentation. Knowing Fafner must be up to something sinister, Lyfia concludes that they must do something to save the villagers. Mu urges Lyfia to take some supplies and return to Aioria while he takes care of the missing villagers. Lyfia is confused as to how Mu will be able to do anything until she sees his cloth box and realizes that he is a Gold Saint.

In another area of Asgard, Taurus Aldebaran has come across a colosseum where a match is taking place. He is surprised to see that the winning warrior is Libra Dōko. After the match, the two saints go to a restaurant and begin discussing why they were revived and who may have done it. Aldebaran is particularly disturbed at the situation, remembering that they had all perished in the Underworld but are now alive in Asgard. He feels that someone is trying to use Athena's saints for a purpose but wonders who would do this and why since the saints only serve Athena. Dohko agrees that someone is using them for their own purpose but admits that, despite his two centuries on Earth, he has never felt more alive than he does now.

Before they can continue their conversation, they are suddenly called back to the arena by the God Warrior Tanngrisnir Heracles. Dohko accepts the challenge but instead says that Aldebaran will fight the God Warrior instead; giving Aldebaran a chance for revenge from when he had been defeated by an Asgardian Warrior.

Back in the village, Fafner is causing unease with his own soldiers until Mu arrives in his gold cloth. Mu demands that Fafner release all of the villagers but the demented God Warrior instead thinks a Gold Saint would be more useful to his experiments instead of regular people. The soldiers attempt to seize Mu but the Aries saint is able to knock them back with his psychokinesis abilities. This discovery greatly amuses Fafner and he launches an attack with the proclamation that a Gold Saint will be no match for a God Warrior. Mu attempts to block Fafner's whip with his Crystal Wall but the barrier is shattered and Mu is knocked down. Mu realizes that Fafner's cloth has an advantage in Asgard and Fafner proceeds to make Mu his next specimen.

At the arena, Aldebaran dons his cloth for the fight. Eager to face the Taurus saint, Hercules attacks but Aldebaran remains still in his traditional pose. Frustrated that Aldebaran is not moving, Hercules tries another attack but only gets the same result from the Gold Saint.

Back in the village, Fafner has managed to successfully capture Mu and begins to torture him for the sake of his experiment. At the colosseum, Hercules questions why Aldebaran does not fight back. Aldebaran answers that he will not fight as long as he remains in the dark about his arrival and purpose in Asgard. However, his greatest reason is that he is following Athena's wish about saint not partaking in personal duels. Angry that the saint will not fight back, Hercules decides that he will force Aldebaran to fight and purposely directs his next attack directly at a small crowd of people watching the match. Aldebaran quickly moves into place to take the attack. At the temple, Fafner is pleased with how Yggdrasil appears to be more energized thanks to feeding off Mu's cosmos. At this time, Mu is able to tap into the consciousness of Yggdrasil and obtain some information.

At the remote cabin, Aioria awakens when he feels a cosmos. Lyfia appears and is thrilled to see the saint has regained consciousness and appears to be healed. She quickly informs him that she met with Mu and how he has planned to free the captured villagers. Continuing the fight, Hercules believes that he had triumphed and defeated Aldebaran. The Asgardian tries to make Dohko his next opponent but the Libra saint points out that the current fight is not done and that Aldebaran's cosmos is actually getting stronger.

Fafner continues to torture Mu and feels that he has gotten all he can from the Aries saint. However, Mu reveals that he has manipulated Fafner into thinking he was in control of the situation while Mu was actually using his psychic powers to get better insight on Yggdrasil. Mu then easily breaks free from his constraints to face Fafner.

Aldebaran decides that he is not going to look too deeply into the reason for his resurrection. Opposite of him, Mu admits to Fafner that he must gather information first in order to decide what to do next. Seeing that Mu still has power to spare, Fafner tries to attack but Mu is able to stop him before he can.

Aldebaran allows his cosmos to rise to a higher level and Dohko notices that his broken horn is replaced with a restored piece. As Hercules tries to attack, Aldebaran unleashes his own attack and manages to beat a stunned Hercules back. Fafner attempts to reminds Mu that he will not be able to overpower him since he is given the advantage for being an Asgardian warrior. Mu instead replies that Fafner is the one who has forgotten valuable information and reminds him that the Aries saint is not the only Gold Saint.

Aioria arrives and this causes Fafner to retreat from the area. At the same time, Hercules removes himself from the fight with Aldebaran. Aioria is upset that Fafner has escaped but he and Lyfia quickly hurry to Mu when he appears weakened from the fight. A short time later, all of the imprisoned villagers have been released. As the people celebrate their freedom, Mu informs Aioria and Lyfia that something evil is growing inside of Yggdrasil. Lyfia guesses this is the reason why Hilda had informed her the tree needed to be destroyed. Certain of their next move, everyone agrees they must make their way to Yggdrasil.

In the post credits scene, Scorpio Milo is found attempting to get information about the God Warriors from a soldier. To Milo's surprise, he learns that the God Warriors are not only close by but that another Gold Saint is as well.

Characters

 * Leo Aiolia
 * Lyfia
 * Sagittarius Aiolos (cameo)
 * Aries Mu
 * Libra Dōko
 * Taurus Aldebaran
 * Níðhöggr Fafner
 * Tanngrisnir Heracles (Debut)
 * Scorpio Milo