Unholy_Angel
Before going into the nine realms, I think it would be better to focus on some of the more mystical places of Earth/Terra/Midgard or however you want to call it. The perfect set up would be where MC gets the Gate spell wrong or interrupted and is sent to a 'dungeon' on Earth. In the Overlord (Yggdrasil) framework, all dungeons are places that exist on top of ley lines or places of power (also monuments and world wonders) that are inhabited by monsters. To get a better idea, Hogwarts from Harry Potter would be considered a 'conquered' dungeon because the area is extremely dense in ambient mana with servant monsters (House-Elves, Merpeople, Giant Squid, and to a lesser extent Centaurs) on top of 3 or 4 ley lines supplementing the wards with their magic from the Earth itself. To me the best possible locations that would be drawn in would be El Dorado in the Amazon Rainforest, Isle of Avalon in England, and Tuatha de Danann somewhere in Norway or Sweden which is the home of the Summer and Winter Faerie Courts.
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