The Starfish is an elusive enemy, appearing only in Super Princess Peach. It is a reference to the video game character Starfy, as the glossary describes it as "a star-shaped foe rumored to be the prince of a kingdom", which Starfy is, as well as it having his running, spinning, and swimming animations. It has pink cheeks and wears black sunglasses, referencing Starfy's hobby of wearing and collecting sunglasses.
Although the Starfish does not attempt to harm Princess Peach, she still takes damage when coming into contact with it. The game describes it twice as an enemy; in the game's glossary, it is described as "a foe", and in all its locations, there is a message box stating it to be an "odd enemy".
Out of all the enemies in the game, the Starfish is the hardest enemy to find and defeat. It appears in a specific area within three levels: 2-5 in Hoo's Wood, 5-5 in Wavy Beach, and 6-4 in Gleam Glacier. There is a low probability of seeing the Starfish when the player enters the specific area it is located, so repeated entry to the area might be needed to cause it to appear. To defeat it, players must attack it in each of these three places. After defeating it in all three places, the Starfish will be added to the Glossary. Once it takes damage in an area, it will not appear in that area again.
In Hoo's Woods, it swims back and forth in a shallow area of water, and eventually will jump up into the sky and leave. Players must hit it or jump on it as it jumps up.
In Wavy Beach, it is asleep on the sand. The player must walk slowly up to it, then attack it, so it does not wake up and flee. It has a mat on it, and upon waking it up, the mat is lifted up, showing a drawing of Mattel on it.
In Gleam Glacier, it stands on a ledge above the player. It will leave after a few seconds. To reach it, players must use the Gloom vibe.
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