Crazy Diamond is humanoid, with a powerful build and tall stature (about two heads above Josuke).
It is clad in tall headgear, part of a mask (occasionally resembling a Corinthian helmetW); and armor-like plates on many large surfaces of its body, similar to the armor seen on The World. Cables join the back of its head to its upper back. It bears a heart motif between the top of its head, its chin, shoulders, celiac plexus, belt, and knees; with pairs of short spikes protruding from its shoulders and ankles.
Its most common color scheme consists of a bubblegum pink interior and light blue or silver armor.
During his first appearance, it had multiple irides with a ripple-pattern on its eyes, and its "flesh" and armor seemed to be inverted in which layer of it they resided on, giving its "flesh" the appearance of some sort of membrane.
Toward the end of part 4, Crazy Diamond was depicted in a small handful of pannels with a small nose visible underneath its helmet.
Crazy Diamond has no personality apart from seeming angry during fights and shouting its Stand Cry "DORARARA ..."; similar yet uniquely distinct from that of Stands belonging to other Joestars.
Likely due to Josuke's own gentle yet rough nature, when treating living things, Crazy Diamond will open its hands to gently touch the target, while during urgent moments or repairing inorganic substances, it will strike with its fists.
Super Strength: Crazy Diamond possesses immense physical strength, having been able to easily punch through the abdomens of two people at once. Its strength matches that of a Star Platinum weakened by 6 years of being unused, having once successfully broken its defense and prompting Jotaro to remark that Star Platinum in its unused state would have difficulties against Crazy Diamond in a contest of strength.
Super Speed: Not only is it capable of surprising an on-guard and fully charged Red Hot Chili Pepper, but Crazy Diamond can also outpace other Stands such as Highway Star in close combat. Josuke estimates that its strikes exceed 300 km/h (190 mph), though this is likely false as his speed is comparable to Star Platinum, which moves at the speed of light. It was also able to catch a bullet fired in close proximity to Josuke.
Precision: According to Jotaro, it can effectively fire off a rifle bullet from its fingers up to 50 to 70 meters when Josuke concentrates.
Thus, Crazy Diamond is a powerful Stand in close-quarter combat whose capabilities are enhanced by its unconventional power of repairing broken items, making it a redoubtable and unpredictable Stand in a fight, but also an invaluable fighting partner as it can effectively heal any wound.
Crazy Diamond's unique ability is to restore or revert objects or organisms to a previous state in their history through touch.
It can repair damage, heal injuries, revert chemical changes and complex structures to their raw components (e.g. a plate of spaghetti back into its raw ingredients). It may also fuse objects, for example, a person with a rock (as with villain Anjuro Katagiri). When restoring a divided object, the user is able to control which part acts as the starting points for the rest to gather towards. Feats of this nature include trapping an enemy by restoring pieces of a broken crate around him; exposing a Stand formerly bound to an object; and tracking by restoring a severed hand, forcing it to seek out and reattach itself to the body from which it was cut off.
If this ability is used while Josuke is in a foul mood, its target may become warped as a result of improper restoration. Crazy Diamond's ability cannot heal its user, cure illnesses (as victims are not considered damaged), retrieve things erased by The Hand, or restore life to a dead organism.
In one of the commercial break bumps for Diamond is Unbreakable on Toonami, T.O.M. uses Crazy Diamond's original name instead of its localized name.
In one episode, Josuke's shown playing the game, "Oh! That's a baseball" where all the members of Jaguars team resemble Crazy Diamond (shown briefly for a second), which is customized by Josuke. Similar to Jotaro and Telence T. D'Arby making their team members resemble their respective stands in their battle in Stardust Crusaders.
↑Love Deluxe - Vol.14 "Shueisha Jump Remix Diamond is Unbreakable Edition" P86 The origin of STANDS! Part 2