Achtung Baby

Achtung Baby (アクトン・ベイビー) is the Stand of Shizuka Joestar featured in Part IV: Diamond is Unbreakable.

Appearance/Personality
Achtung Baby is bound to its user's own body, granting her the ability to turn invisible. Because of that, its physical manifestation is never shown, nor is there any trace of personality.

Abilities
Invisibility: Achtung Baby has the power to render its user invisible as a protective measure. Depending on Shizuka's stress level, the active strength of the stand can increase making the immediate surroundings of the child invisible as well, be it a person's fingers, her baby carriage or even the ground. At its full power, it makes everything in a several foot-radius invisible.

The invisibility status may last on the affected subjects even when they are already removed from Achtung Baby's ability range. As shown that the the ground, trees and stones continued to stay invisible after the carriage which was carrying Shizuka had gone pass them while her ability was active, leaving a trail of objects with visually voided portions. Similarly, Joseph's hands turned transparent from holding Shizuka as she was disappearing, which the effect persisted to after he had put her into the carriage. This seems to only happen when Shizuka becomes extremely stressed and completely loses the control over her power as a result. Should her emotional state be recovered, objects that were turned invisible by the ability will also return back to normal.

The shape of her invisibility can change as well, as shown when she was dropped into a pool and Joseph slitted his wrist in order to use his blood to locate her, the shape was that of a sphere.

Trivia

 * The artbook JOJO A-GO!GO! incorrectly lists its name as Achtug Baby.
 * The term "Achtung" is German and translates "Attention/Caution".