After resolving the incident in Astral City, you’ll have to head towards Purgatorium next. From Astral City, take a ship ride back to Tatroi.
Leave Tatroi and follow the road until you reach a fork in the road. There’s a port town called Tropp, in the southwestern tip of the continent. You can stop over there if you want and resupply as needed.
You don’t have any official business in this town for now. However, if you did visit the town, enter the house in the east part of town to obtain ?Item.
Back in the world map, continue following the road heading north until you find the Highland Caves entrance. Enter the cave. There’s no items of interest here so just follow the route until you reach the exit.
After exiting the Highlands Cave, you’ll be back on the world map. You can find the Purgatorium’s main entrance. We will check out secret entrance next but for the meantime, just head inside.
Head north until you reach the structure’s interior. Head to the left to get ?Herb from the chest.
Return to the previous screen. You can enter either the door on the upper-right corner or directly to the right, since both lead to the same corridor. In that screen go to the door in the corner (between two angel statues) and pull the switch there.
Return to the main room and take the upper left door this time. Examine the glowing crystal to get 50SP. (Applied to everyone in the party)
We are done here for now. Exit the Purgatorium and go around the mountain to the northwest to find Purgatorium’s other entrance.
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