Season 1
Gainer lives in a Domepolis in Siberia. One day, he is unexpectedly taken to a detention center by the Siberian Railway Guards on suspicion of emigrant activity. There, Gainer meets a young man named Gain and leaves with him when he escapes. They break into a manor house and Gainer steals an Overman to fight back against the Railway Police who have caught up with them.
01. Gain and Gainer
Gainer Sanga, a skilled gamer, leads a normal life in the domed city of Yapan until he gets involved in a mysterious altercation, leading to the activation of an Overman.
02. Repayment
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03. Explosion! Overskill
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04. The Taste of Victory is the Taste of a Kiss
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05. Eyes Shining Toward Siberia
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06. Saint Reagan's Assassin
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07. The Railroad King, Kizz Munt
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08. A Hellish Relay Race
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09. A Hard Struggle! Adett, the Teacher
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10. Asham's Tenacity
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11. Tears Can't Be Stolen
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12. An Attack Over Enormous Stone Columns
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13. Brunhilde's Tears
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14. The Apparition, Dominator
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15. Between the Schedule and Magma
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16. A Tough Fight, Adett Squad
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17. A World Without Lies
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18. The Sword's Fragility
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19. Leonetta's Nightmare
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20. Defeated at Katezu
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21. Overman's Darkness
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22. The Agato Crystal
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23. Overdevil Revival
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24. Overmax
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25. Inside the Ice
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26. Gain Over
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