The vilest names in Allah’s sight on the Day of resurrection will be that of a man called Malik al-Amlak.

Abu Dawud said: This tradition has also been transmitted by Shu'aib b. Abi Hamzah from Abi al-Zinad through different chain of narrators. This version has the words "akhna' ismin" (most obscene name) instead of "akhna ismin" (the vilest name).

Sunan Abi Dawud Book 43, Hadith 189