Sea Mauville is a half-sunken decommissioned research facility located north of Route 108. It features a side-quest involving the ships’ locked rooms and finding various keys, ultimately leading to a storage room filled with rare items.
Within Sea Mauville, you can also encounter Spiritomb and the legendary Pokémon Lugia(AS) and Ho-Oh(OR).
The table below summarizes where each room is, but follow the link above for a step-by-step tutorial on where to find each key along the way.
Room No.
Exact Location
Room #1
Room #2
Room #4
Room #6
Storage Room
Legendary Encounter – Lugia or Ho-Oh
The portal in the control room
The portal on the ship’s deck
After obtaining the Tidal Bell(AS) or Clear Bell(OR), a portal will appear somewhere in the ship.
For the Tidal Bell it will be at the control desk in the underwater control room, and for the Clear Bell it will be at the end of the beam on the ship’s exterior deck. Interacting with the portal will initiate a battle with Lugia or Ho-Oh, respectively.
Lugia (AS)
Level
Lv.50
Type
Psychic / Flying
Ability
Pressure
Held Item
None
Moves
Rain Dance
Hydro Pump
Aeroblast
Punishment
Ho-Oh (OR)
Level
Lv.50
Type
Fire / Flying
Ability
Pressure
Held Item
Sacred Ash
Moves
Sunny Day
Fire Blast
Sacred Fire
Punishment
Special Encounter – Spiritomb
Trying to find Spiritomb
After capturing/defeating Kyogre or Groudon in the Cave of Origin, you can encounter Spiritomb in Sea Mauville.
Just find and enter the southwesternmost room of the east corridor. As you enter, the message “It feels as though you’re being watched” will appear.
To encounter Spiritomb, stand in the northwest corner of the room and open a menu, then immediately close it. This will cause the Odd Keystone to appear, triggering a battle with Spiritomb.
Note: If you accidentally defeat it, Spiritomb will respawn after you re-enter the Hall of Fame. This works the same for all legendaries in the game as well.
