Yuno vs. Gaderois is a fight that occurs in the Golden Dawn base.
Pre-Fight
To capture William Vangeance and gain his World Tree Magic for the Spade Kingdom, Dark Triad member Zenon and his two Dark Disciples, Gaderois and Foyal, attack the Golden Dawn Base. Easily tanking the attacks made by the Golden Dawn, Foyal and especially Gaderois proceed to attack the Golden Dawn per Zenon's wishes. Gaderois proveeds to slaughter a great number of them including Siren Tium. Yuno, who was notified about the attack on the Golden Dawn Base, hurries back and finds Gaderois standing over his dead or severely injured Golden Dawn comrades. Gaderois notices Yuno and condescendingly states that Yuno, a gnat, is looking down on him. Yuno immediately uses Spirit Dive and angrily demands answers from Gaderois on what he did to his comrades
Fight
Yuno has a flashback to when the other Golden Dawn members apologize to him about how they treated him for being a peasant. They all resolve to work together to better help the kingdom.
Gaderois informs the angry Yuno that half of his comrades are dead while the others are just barely alive. Yuno immediately uses Spirit Storm on Gaderois who blocks and destroys the spell stunning Yuno. Gaderois launches multiple projectiles at Yuno, who uses Spirit's Hushed Dance to save his injured comrades. Gaderois notes that Yuno's abilites and that he is a Stage Zero mage which makes the fight more interesting for him. Gaderois introduces himself and asks for Yuno's name which Yuno refuses stating how he won't give anything to a monster like him. Gaderois and Yuno begin fighting with Gaderois being able to injure him significantly.
Gaderois begins to praise the strength of Zeno and the other Dark Triad members as well as gloating about how they killed their previous, peace-loving king, who unbeknownst to him was Yuno's father. Yuno, who was stunned and somewhat upset by these remarks, asks Gaderois what feels when he kills people. Gaderois responds with a devilish smile that the destruction and fights he is involved with are all thrilling and exciting to him and accuses Yuno of being the same as he lunges at him. Yuno, enraged by Gaderois's remarks, uses Spirit of Zephyr and attacks Gaderois. Though he was able to block the spell, Gaderois notices that Yuno is accelerating his wind to break through his stone armor. Yuno states as he cuts through Gaderois that regardless of his status as a magic knight of the Clover Kingdom or a Prince of the Spade Kingdom that he will break the system of Curses that divides the world.
Post-Fight
Gaderois's magic disappears and he falls down either dead or unconscious while Yuno moves on to aid Klaus Lunettes and Letoile Becquerel in their battle against Foyal, the other Disciple Zeno brought.