Sploosh! is a quest in Mario Party Advance that is given by Sushi, who is panicking at Sushi Cliff due to someone falling off of the cliff and into the surrounding ocean. If the player decides to help, the quest promptly begins, though they also have the option of quickly leaving Sushi alone, causing him to become angry for ignoring his calls for help. Once the quest begins, Shroomlock suddenly jumps out of the water onto the nearby cliff, and explains that he was pulled into the water by an unknown person. Sushi says that he didn't see anyone pull Shroomlock, but there were also three witnesses (Blooper, Dolphin, and Cheep Cheep) who were near the cliff at the time of the incident. Shroomlock suspects one of the witnesses of being the culprit, as criminals tend to stay at the scene of their crime, and asks the player to find the guilty party. Sushi, having already interviewed each of the witnesses and remembering exactly what each of them said, relays their stories to the player (which also makes it unnecessary for the player to interview the witnesses themselves):
Emphasis is placed on the fish characteristics that they mention: tentacles for Blooper, fins for Dolphin, and gills for Cheep Cheep. Out of the three of them, Blooper is the only one who has the proper appendages for pulling, making him the culprit. If the player names either Dolphin or Cheep Cheep, Shroomlock disagrees and says that they're innocent, and as the player was unable to solve the crime, Sushi kicks them out and forces them to restart the quest from the beginning. Once the player names Blooper, he immediately appears and asks why he was accused. Shroomlock then explains the logic to him, causing him to admit that he was responsible. He justifies himself by saying it was a prank, and Shroomlock lets him leave without any punishment. Blooper thanks him and swims off, Shroomlock walks away to pick up some groceries, and Sushi is so impressed by the player's crime-solving skills that he gives them the Digitizer Gaddget. The quest is finished once Sushi thanks the player again for their help.
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