My perception has always been that that game was under-appreciated. Nice to run into a fellow appreciator. I think it's also the only DRM[0] I've ever encountered that was a genuine pleasure to use (not that it would work today).

[0] - Conquests of the Longbow required you to use the book that came with it to look up lore like coats of arms, to identify plants by their leaves, find out about superstitions around gemstones, etc in order to solve the puzzles in the game. At the time, people generally pirated by passing around floppy disks, none of the kids pirating had access to xerox machines, and the information in the manual was obscure, so you really kinda needed to have the manual. But if you did have it, it almost felt like a natural part of the game, and the information was fun to learn. Of course, now you can easily find it online: http://www.sierrahelp.com/Documents/Manuals/Conquests_of_the...

The BBC game Exile had a "novella" that came with it - the story of how things came to be before the player arrives. The copy protection had you look up a page number, line number, word number to proceed. Fun stuff. (I just found the text! http://inventivity.co.uk/exileami/novella.htm) (And the game! http://bbcmicro.co.uk//jsbeeb/play.php?autoboot&disc=http://...)

In fact, how they squeezed what they did out of the BBC B is amazing.

I definitely encountered other games for which you had to look up stuff in the manual, and maybe it wasn't done as well because I always hated it.

I enjoyed it for Ultima VII, where the manual was written as a holy book / biography of the main religious figure (antagonist) of the setting. You needed to answer questions from the book to be allowed out of the starting town.

I think in King's Quest it was looking up some specific code word in a random grid or something, before it would let you launch a boat?

King's Quest 5's copy protection (floppy version only) was enforced with a requirement to use a magic wand to cast a "spell" at various points in the game, where the "spell" is a series of letters that the player matches to symbols in the printed manual. Launching the boat was one of the points in the game where this was required.

https://kingsquest.fandom.com/wiki/Crispin%27s_wand#Behind_t...

Yup, CotL was uniquely well done.

Wing Commander made you look up ship schematics to answer trivia. I was maybe 10 years old and got a copy from the son of a family friend but he only gave me photocopies of a few of the pages, so it sometimes took a while before I could get in!

Loved that part too, was really confusing at first, because I was not aware that the manual might have a use at all. I think the files are on the game creators webpage, there was even a photo of her at the back of the box.