A lot of folks mentioning Madvillain here but he went by a couple of other monikers too, also producing incredible albums:
King Geedorah - Take me to your leader [2003] https://open.spotify.com/album/1mrhahrlJu5JfzgeV6Cy8t?si=KqY...
Viktor Vaughn - Vaudeville Villain [also 2003] https://open.spotify.com/album/7HPjcPD2cr8E5oHvVAmBp7?si=sJM...
If you haven't heard these yet I highly recommend checking them out.
His music was a huge part of my early adult years and this news was a surprising and sad way to end the year :(