The Commodore 128 was a version of the Commodore 64 that also had a Z80 CPU along with its "native" 6502 CPU so the system could run CP/M as well as C64 software. (As well as more RAM and other differences.)
But were there ever any games that ran on the C128's Z80 as the main CPU?
If not games, demos or other software that ran on the metal rather than within the CP/M system.
Obvious examples would be ports from Z80-based systems such as the ZX Spectrum.