A wisp is a small ghostly mob that resembles a baby ghast. However, there are differences. While a baby ghast has a translucent body, a wisp's top texture resembles the blue block within beacons found within the base game, while the rest of its body has a light blue color. A wisp's eyes and mouth have the darkest shade of blue. The eyes also appear to bleed over the edge of the face and onto the side of the texture. There is a small white line texture below the eyes and the mouth, while there is also a subtle blue line above both of the eyes, lighter than the eyes and just barely slightly darker than the rest of the face. A wisp appears to have a white 2D texture for it's arms, and a light blue 2D texture for its legs. A wisp appears to be floating due to its visible arm and leg appearing as if it were moving back and pointing down. A wisp's eyes and mouth appear to be wide open.

https://minecraft.fandom.com/wiki/Minecraft_Dungeons:Wisp