Ep 10. Guardians

Astro wakes up in the Heart Kingdom after his encounter with Mars and Fana. He is greeted by the Queen, who informs him that he is safe in her kingdom and that his friends have gone ahead to the Diamond Kingdom. Meanwhile, Yami and the rest of the Black Bulls have infiltrated the Diamond Kingdom's castle in search of the magic stone.

The group splits up to cover more ground, with Yuno and Luck taking on some guards while Noelle and Finral search for the stone. However, they soon run into opposition in the form of two powerful mages named Mars and Ladros. Despite their efforts, Noelle and Finral are quickly overpowered and taken hostage.

Yuno and Luck also find themselves struggling against Mars, whose powerful earth magic makes him a formidable opponent. Just when it seems like all hope is lost, Asta arrives on the scene and joins the fight. With his anti-magic sword, Asta is able to neutralize Mars' spells and give Yuno and Luck an opening to attack.

Meanwhile, Noelle and Finral manage to escape their captors and go in search of Yuno and the others. They stumble upon a room filled with prisoners, including an old friend of Yuno's named Klaus. However, before they can free anyone, they are confronted by Ladros, who has absorbed the magic stone and become nearly invincible.

Back in the main battle, Asta manages to take down Mars with a powerful blow from his sword. However, Ladros proves to be a much tougher opponent, shrugging off their attacks and capturing Asta. In a last-ditch effort, Yuno and Luck combine their spells to create a tornado that throws Ladros off balance, allowing Asta to break free and land a finishing blow.

With the magic stone secured, Yami and the others make their escape from the Diamond Kingdom. However, they soon realize that something is wrong with the stone, as it begins to glow ominously and emit a powerful aura. Back at the Heart Kingdom, the Queen also senses the disturbance and warns Asta that they may be facing a great danger.

Overall, "Guardians" is a thrilling episode full of intense battles and exciting plot developments. The introduction of Mars and Ladros adds some much-needed depth to the Diamond Kingdom as an antagonist, while the reunion between Yuno and Klaus provides an emotional highlight. The episode also sets up some intriguing new plotlines for the future, particularly regarding the nature of the magic stone and the potential threat it poses.