Satan can't create anything, but he can twist and pervert what already is.
Like homosexuality and other perversions: Jehovah created heterosexual missionary sex, but then Satan jazzed it up by introducing sodomy, BDSM, and 'prostate massagers'.
Jehovah creates cute vegetarian pussycats and Satan turns them into bloodthirsty incarnations of death.
Jehovah created humans to walk around naked and munch on fruit all day, but then Satan fowled everything up with that damn fruit and taught us writing, mathematics, and agriculture (see the Book of Jubilees).
Satan knows he'll never be God. He'll never be able to create anything original so, instead of accepting his inferior status, he contents himself with ruining and defacing what Jehovah has created.