Sealed Chamber
The Regis are a trio of rare Pokemon who reside in tombs scattered throughout the Hoenn Region. These tombs are locked. The three are Regice, Regirock and Registeel. To open their respective tombs, you must travel to the Sealed Chamber and solve the riddles. Afterwards, you can search for the tombs of the Regis, battle them and try to add them to your Pokemon collection. Regice's tomb is in the Island Cave, Regirock's is in the Desert Ruins and Registeel's is in the Ancient Tomb.
Requirements
To access and complete the Sealed Chamber, you need several items. You can't even reach the chamber without having at least one Pokemon that knows the surf ability and one that knows the fly ability. You use these to arrive at the entrance to the chamber. Additionally, you need a Pokemon who knows how to dig. You also need to have Relicanth and Wailord in your party as these two are necessary to completing one of the riddles in the cavern.
Location
To find the Sealed Chamber, have a Pokemon who knows the fly ability take you to Pacifidlog Town. Walk to the southwest corner of the town and then call upon a Pokemon with the surf ability to take you into the water. Travel as far west as you can until you come to an area where dark blue water is surrounded by four rocks. Use the dive ability to go underwater. Keep moving down until you reach the entrance to the Sealed Chamber. Use the dive ability at the entrance.
Messages
The Sealed Chamber contains several messages that instruct you on how to open the tombs of the Regis. However, these messages are coded in braille. The first message you find at the entrance to the Sealed Chamber instructs you to use a Pokemon with the surf ability to get inside. After you enter, several mounds list the keys to translating braille into letters so you can decrypt the remaining messages and unlock the tombs.