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Serene Sea (Japanese: しずかなうみ Serene Sea) is a Friend Area in Pokémon Mystery Dungeon: Red Rescue Team and Blue Rescue Team. It is available for 8,000 from Wigglytuff in Pokémon Square. It is in the Northern Ocean, and has a capacity of four Pokémon, all of them Water-type. Upon buying it, the player gains access to the Grand Sea and Far-off Sea dungeons.
Serene Sea appears to be some sort of underwater ruin reminiscent of Atlantis.
An infinitely calm sea without waves. Large Pokémon live luxuriantly here.