|Where||Towards the right in the Hidden Lake|
|Opened|| Cave Expedition|
March 15, 2010
The Underwater is a special members-only room located beside the Hidden Lake. It can only be accessed by following the Giant Squid's shadow in the game Puffle Rescue. After a penguin has followed the shadow, the penguin gets in this room and can then come back whenever they like if they get the Moss Key Pin. Although there are no games to play in this room, the game Puffle Rescue leads to it.
This room was first opened as a members only room during the Cave Expedition. There was a free Coral Reef Background attached to a rock. The background is no longer there and has been replaced by the Moss Key Pin, which is available in the exact same spot. The room reopened on March 15, 2010 and is only accessible by members. On January 19, the seahorse and the fish gone.
During the Cave Expedition.
- This is one of three member-only rooms that are always available.
- Club Penguin removed the fish, seahorse and the pin (now seen only when you haven't got it yet) to make the game load faster
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