|“||Kuh kuh kuh... Welcome to the world of Dark Blue Moon... The ocean!||”|
—Impostor Captain Tennille, Chapter 129
Dark Blue Moon is a humanoid Stand with aquatic features. It manifests itself as some sort of merfolk-like entity with a flat head, four eyes, a large dorsal fin lining most of its back, additional fins on its legs, and webbed hands and feet.
According to JOJOVELLER, his form was made while thinking of a combination of vital strength and of mineral material.
Befitting its name Dark Blue Moon is consistently portrayed across media as being blue with red articulations.
Dark Blue Moon displays little to no personality by itself. It represents the Tarot Card The MoonW, which symbolizes trouble in water, lies, betrayal, and fear of the unknown. This symbolises both the way Impostor Captain Tennille deceived the Joestar Group, as well as the nature of the Stand itself.
Dark Blue Moon is a marine Stand, and, as such, its skills are more effective in an aquatic environment. It is probably less effective in a terrestrial environment, but this is unknown.
Dark Blue Moon has a high enough range that it was able to attack Jotaro without the user even being in the water. Its user has stated that it swims faster than any fish in the sea, a trait proved to be true when Dark Blue Moon managed to create a giant whirlpool by simply spinning its webbed feet fast enough.
Its Stand User also has an incredible lung capacity, being able to hold his breath for up to a personal record of six minutes and twelve seconds, which helps the Stand to maintain a battle, even if the user is thrown into the water.
Dark Blue Moon's hands are strong and sharp in water, making them effective weapons. Because of their sharpness, they are strong enough to destroy a still-running engine propeller and slice a shark in two with ease.
Dark Blue Moon can also use its scales as projectiles, throwing them against the enemy. These scales were sharp enough to cut Kakyoin’s hand when he tried to enter the water. 
The barnacles drain the target of its strength and also allow Dark Blue Moon slight control over the infected body parts, allowing it to drag its foes back into the water if they try to escape it.
Chapters / Episodes
Chapters in order of appearance
Episodes in order of appearance
- ↑ 1.0 1.1 1.2 Chapter 128: Dark Blue Moon (2)
- ↑ 2.0 2.1 2.2 2.3 Chapter 129 Dark Blue Moon (3)
- ↑ Chapter 127, Dark Blue Moon (1)