Tusk

Tusk (牙 (タスク)) is a stand ability featured in Part VII: Steel Ball Run. Similarly to Echoes from Part IV: Diamond is Unbreakable, Tusk evolves into various forms.

Ability
In his first form, Tusk gives Johnny the ability to "spin" his fingernails at high speeds and use them as projectiles. Once Johnny shoots a fingernail, it grows back extremely fast.
 * Quick-Spin Nails

Ability
Once Johnny learns to spin the fingernails with aureal rotation, thus bringing Tusk to his second form, he can make the holes he produces move: if for example he shoots and produces a hole on a table, he can move the hole on the surface of the table and whatever touches the table's surface. However, the hole leaves a track behind it as it moves. When Johnny shoots a fingernail with aureal rotation, the fingernail takes several minutes to grow back; however, Johnny discovers that by munching herbs or drinking tea he can accelerate the growing process.
 * Ten-Aureal Nails

Ability
During the fight against the stand Civil War, Johnny, in a moment of deep crisis, sees Jesus, who gives him the hint that leads him to discover the third form of Tusk. By shooting himself with a fingernail spinning with aureal rotation, he's able to send a part of his body through the hole, moving it away from his body. This way he can shoot fingernails from different directions, sending his hands or fingers through the holes.
 * Through The Hole

Ability
Johnny unlocks Tusk's fourth and final form after receiving Gyro's fifth lesson. The principal behind the technique derives from the use of the Super Spin, which requires Johnny to allow his horse to run in its "natural state". By doing so, the horse produces rotational energy in the form of the Golden Rectangle and by combining it with Tusk, Johnny is able to release infinite rotational energy. Because Act IV derives from his horse's running power, Johnny is typically only able to use it when on his horse. He can, however, shortcut the process as a last ditch effort, using a steel ball to temporarily galvanize his horse's movement.
 * Infinite Rotation

This Super Spin can pierce through other dimensions and control gravity to some extent. The damage caused by the rotation is also infinite and will not end unless Johnny were to apply another similar rotation moving the other way, resulting in them canceling each other out.

When hit by one of Johnny's nail bullets, Tusk Act 4 can insert the infinite spinning motion into the victim, making them spin internally. That spin goes on forever and never leaves the person and his/her stand, forcing him/her to return to the place where he/she was hit, or its equivalent in each parallel dimension. Tusk can move through D4C's Love Train & stopped time to attack it's enemies. The spin is also transferable between objects, as the Diego Brando from another universe cut his leg off and threw it to Johnny, transferring the infinite rotation to its user. Another example is when Funny Valentine went into a passing car trying to run away from Tusk, the infinite rotation nearly instantly destroyed it, coming back to Valentine.

This ability is likely to be a reference to the Fleetwood Mac song Landslide, as the lyrics suggest the fate of Funny Valentine when experiencing Tusk 4.

Interestingly, ACT 4 punches while making the Kujo family's "ORA ORA ORA" battle cry.

Trivia

 * Tusk (Act 4) is the first stand to have a battle cry in Part VII. This is especially unique due to most of the stands in Part VII being tools rather than humanoids. The second being The World.
 * On occation Tusk's kanji is written as "爪" (Nail), rather than "牙" (Tusk).