The World Ultimate
Kars learns how to understand Dio's The World during their battle and creates his own superior copy. Dio then uses his Beyond with the belief that he's the king of the world, and also awakens The World Ultimate.
The World Ultimate resembles The World with some minor differences. Its headpiece is much wider and the diving cylinders on its back are a lot larger. It also has a wheel on its shoulder. Kars's version of the Stand has a "K" on its chin instead of a heart.
The World Ultimate's full capabilities are not mentioned. Nonetheless, after Dio became an Ultimate Thing, his regular The World was capable of stopping time for nearly an hour. Therefore, The World Ultimate should presumably be able to stop time for longer than an hour.
As soon as Dio is about to use his new Stand, Kars quickly uses Whitesnake Ultimate to shatter the disc of Dio's Stand and it begins dissolving. However, Dio manages to keep The World Ultimate alive by tricking Kars into awakening Made in Heaven Ultimate Requiem and then escaping to another universe where he steals Diego Brando's body.
With the help of Funny Valentine, Kars gets eight parallel world versions of himself to use The World Ultimate to stop time in order to distract Dio. As long as time is stopped, the parallel world versions of Kars are able to be close to each other without turning into Menger sponges from D4C's ability.