If you are looking for the legitimate "Dizzy" experience for guitar tone (which shares the same name in some circles), you may be referring to the Dizzy V4 Silver/Blue

The term "Nulled" indicates that the software's license key or protection has been removed, usually to make a paid script free. While tempting, using a .rar file like "dizzy v4.0 Nulled.rar" from unofficial sources carries significant risks:

: Creators can set up subscription tiers and receive direct payments.