Dire, Dire Docks

Dire, Dire Docks is the ninth course in Super Mario 64 and its remake, Super Mario 64 DS. Like Jolly Roger Bay, this course takes place in and about a large, deep body of water. The entrance to the course is above a large pool of water connected to a submarine dock by an underwater passageway. A variety of marine life, including Sushis and a Manta Ray, live in the first pool. The course is notable as the only course which changes based on the completion of another: Bowser's sub sits in the docking area of this world until Mario defeats him a in Bowser in the Fire Sea, after which Bowser's submarine disappears, the gate blocking the passageway to the pond outside Princess Peach's Castle opens, and moving poles appear in the framework of the docks. Additionally, the level contains 106 Gold Coins, making it one of the most difficult levels to collect one hundred coins in.

Super Mario 64
During the events of Super Mario 64, a flat, watery portal leading to the docks was located in the basement of Princess Peach's Princess Peach's Castle, separated from the rest of the castle by a Star Door. When Bowser invaded the castle, he sealed the door and used the location of the portal to his advantage. After Mario defeated him in Bowser in the Dark World, Bowser retreated to another area, Bowser in the Fire Sea. The connection between the castle and his new hideout was behind the portal to Dire, Dire Docks. Bowser also kept a submarine at the docks.

When Mario broke the spell on the Star Door with the combined power of thirty Power Stars, he jumped into the portal and found himself in Dire, Dire Docks. After collecting the first Star, Board Bowser's Sub, located on top of Bowser's submarine, the portal moved backwards, revealing the connection to Bowser in the Fire Sea. After defeating Bowser there, Mario could return to Dire Dire Docks to find that the sub was gone, the gate to the pond opened, and moving poles were now moving on the ceiling.

Board Bowser's Sub
As mentioned previously, Mario must collect this Power Star he can fight Bowser the second time. Due to the presence of Bowser's sub and other changes throughout the dock area, this is the only Power Star currently accessible to Mario. The hero must dive down into the first pool, swim through the underwater tunnel, find a ! Switch on the dock, and use the blocks that appear for a short time to jump on top of the sub. The Power Star was located at the front of the sub.