I keep getting the same question. 'How do you get Asch?' (Sorry If this was posted already).

Mushroom road
You know how Luke/Asch's mother says "I need to get my medicine but they didn't have the ingredients, I'm fine."
Well apparently Asch goes to Mushroom road to get the medicine, yes the medicine, he went to get the mushroom. So Luke and the others decide to help Asch. Luke stays because he thinks it's useless to have two of the same time. Get the mushroom and leave the other direction! The direction oppisite to the one Luke's in! That way, he stays in Mushroom road and you keep Asch. But, In scenes Luke will still be there, but during battles you'll have Asch.
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Location
Gah... If anyone has a game map please load it onto here so I can circle the EXACT location of the mushroom road.