This opponent is unlocked after successfully Synchro Summoning "Odin, Father of the Aesir". You can also unlock Machina Fortress as a Turbo Duel Opponent after successfully Special Summoning "Machina Force".
In Over the Nexus', Machina Fortress uses a Ground Deck titled "Mobile Cog Fortress" and a Turbo Deck titled "Superspeed Fortress".
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