Remove webs without overlooking the upper rooms
Use the map to identify the rooms still marked with webs. Some can be vacuumed directly, while thick barriers need fire. The precise web counts vary between attempts, so follow the current map rather than a fixed list of numbers. Check both floors of the Library, the Balcony and the newly accessible Rafters before returning to the last marked room.
Carry fire through the mansion
Pull a hanging web ball toward a nearby flame to ignite its connected web. In the Common Hall, use the candles; on the Balcony, use the stove. The Library’s fire painting can provide the flame after Dark-Light restores the missing object. In the Bedroom, turn on the heater and spin the ceiling fan so the hanging web ball passes through the flame. This burns the screen-blocking web and opens the mushroom-shaped gem’s hiding place. Keep away from the burning ball itself.
Finish the Rafters and collect Boothoven
In the Rafters, restore the fire paintings with Dark-Light, including the concealed one behind the cheese picture, then burn the remaining webs. Vacuum the amethyst from the dresser at the far-right end before finishing the map’s final web. For this mission’s Boo, visit the lower Library and restore its missing piano. The English HD name is Boothoven; older 3DS guides call this Boo Ooga Booga. Completing A-5 opens the mansion’s boss mission.
Collectible checklist
Gloomy Manor gems — #12 Rafters, #13 Bedroom
Boo checklist — Lower Library: Restore the missing piano. In the English HD release, this Boo is named Boothoven.