[JeanMarcS]

I remember a text adventure game on Amstrad CPC ("Le passager du temps" in french, roughly translating as "Time passenger") which I had a pirated copy.

You could play the adventure until you found the time travel machine (could take 1 to 3 hours depending).

You start the machine and then it went on infinite loop text : "tired of piracy tired of piracy tired of piracy..." !

Highly frustrating, but you couldn't help to admire the developper.

If I remember correctly, it was something about the way that a floppy track was formated, with the wrong number of sectors, which was readable by the disk drive, but it couldn't write it using normal copy mode.

[lloeki]

Could also be something like that:

https://scarybeastsecurity.blogspot.com/2020/12/the-cleveres...

I remember reading some article I can't find again about a very unusual floppy protection that involved nonstandard floppy format, something like non standard sector sizes that could be read by the hardware but not written, and the protected software implemented some direct access to the floppy hardware to read data.

[ornornor]

Settlers III did something like that too.

If you were running a pirate version (or a poorly cracked one), the game would run just fine but at some point, it would only produce pigs instead of another resource (can’t remember which) and you were basically stuck because you couldn’t get the more advanced buildings etc without that resource.

[mtrower]

Original SimCity would let you play off you failed the copy protection, but would Chuck disasters at you left and right.

Downright sadistic tbh.