[MarkMoxon]

It is in-game, but it is astonishingly rare. Specifically, there is a 0.011% chance of spawning a Cougar during each ship spawning routine, which is around 1 in 9000 ship spawnings

And it's got a cloaking device so it doesn't appear on your scanner.

Anyone who has genuinely seen one of these in-game is a really lucky commander!

Lots of details here:

https://elite.bbcelite.com/deep_dives/the_elusive_cougar.htm...

[another2another]

Hmm, I wonder if that's what the second mission was to find?

I played it on the CBM64, and seem to remember being given a mission to find a stealth ship. Flew around loads, but never found it as far as I can remember.

[MarkMoxon]

No, the Cougar is nothing to do with missions (in the 6502 versions, anyway - the other platforms have different mission code). It's just a rarely called part of the random spawning routine. Very rarely called.

The mission-related ship is the Constrictor, which you only bump into at the end of that mission.

Obligatory link: https://elite.bbcelite.com/deep_dives/the_constrictor_missio...