What happened to Belshazzar on the night of the writing on the wall?

Answer: He was slain

That very night Belshazzar king of the Chaldeans was slain, and Darius the Mede received the kingdom.

“That very night Belshazzar king of the Chaldeans was slain, and Darius the Mede received the kingdom at the age of sixty-two.”— Daniel 5:30-31 (BSB)