From Dragon's Peak flows the Dragon River to Squirtle Lake which then empties out into a southbound river that runs all the way down here, the Shallow Marsh, eventually continuing down into the River Delta. The river is wide in this area, where the water gets much more shallow and runs slowly across the land, forming the marsh.
This is the start of the forgotten corner of Arcea. There are no roads to Shallow Marsh and all the packed dirt pathways built on the marsh water were made by locals. The pathways change often as the path breaks up and is carried away to the River Delta.
Of course, the region being so remote and forgotten makes it an ideal hiding place for outlaws. Or it would be, perhaps, were it not so close to the Quayoffi border. The only thing that worries a bandit more than an Arcean prison is a Quayoffi one. Still, the occasional band of ruffians can overtake the marsh and make it a nightmare to travel across.
Generally, the only folklore about Shallow Marsh comes from the reclusive local Poke'mon of Taeriana village and they rarely share their stories with outsiders. The only one that's ever been told and recorded was of 'Mud Poke'mon'. They were Poke'mon of the faith who later turned to petty crime and actions that'd anger Arceus and thus would be turned into mud creatures to forever wander the slop where they belonged, attacking outsiders by rising from the dark and the water.
Oftentimes rebellious youth of Taeriana will be disowned or cast out and meet up with nomadic gangs of outsiders. These cast-out youngsters will take the story of 'Mud Poke'mon' to heart and become one. They'd often call themselves 'The Mud Boys'.
The term 'Mud Boys' is often incorrectly associated with being a specific gang but it instead refers to any Poke'mon cast from Taeriana that takes up banditry in Shallow Marsh.
During their adventures to Taeriana to get a Dove Fo Uddjo voucher, Team Azure had to cross the Shallow Marsh only to run into the Mud Boys that had taken up residence there, ready to ambush the novice guild team!
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