Sometimes I look at my X68000 games collection, and while the games I have (120 retail games or thereabouts) are by and large wonderful, I often think about the games that WEREN'T on the system, and I wish that they had been. Especially those that were available on other systems (Amiga, Atari ST, even 8-bit machines)

For instance:

Sega System 24 games: We got Bonanza Bros (bizarrely runs at 15 and 31kHz, but not 24), but no Crack Down, Gain Ground or Scramble Spirits.

Toaplan games: Kaneko planned to release Same! Same! Same! and Tatsujin on the machine, but never did. A tragedy.

Taito classics: We got Bubble Bobble, Fairyland Story and NewZealand Story, but no Rainbow Islands, Pulirula, Mizubaku Daibouken or Don Doko Don. Rainbow Islands would have been dynamite.

Arcade racing games: We got Super Hang-on, Full Throttle and an abominable Chase H.Q. No Outrun? Maybe they decided a less-than-perfect version was unacceptable. It was on every other machine. No Enduro Racer?

Geoff Crammond's F1GP on Amiga and ST was sensational, Overtake is ok.
Microprose did release other games on the machine, too.

Double Dragon, Shinobi, Splatterhouse, and many more.