I figured out how to solve it, but didn't actually sit down to crack it.

I don't think you could come up with a 'right code for the right game, wrong code for Duke 3D' scenario, since you really don't know where people will go wrong. We all mess up in different ways.

Sometimes figuring out the path is satisfying enough. Well done.

Consider a choose-your-own-adventure story. You could write one such that every incorrect choice eventually results in a fatal fall down some stairs. So it's a question of constraining how the solver can fail. Granted, the reader could still drop his book in the bath or suddenly forget English, but I imagine we could build a puzzle where all reasonable failures lead to Duke3D.

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Aha, Austro, thanks for the unusable code! That's a solid idea. I should've thought of that as I encountered your Steel Sky code recently... you can probably guess how.

Bummmp.

I'm still stumped, but I want someone else to redeem this so I can see the solution.

(I shouldn't have tried to redeem that, I can't clean myself up now)

Since no one else seemed to want it, I decided to go ahead and redeem the code. Thanks for both the fun puzzle and the prize!

SPOILERS AHEAD!

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Each entry in the puzzle is an anagram of a game in the GOG catalog, with one letter (or several, more on that later) missing. The missing letters give you the code.

The numbers in parentheses were there to ease the job of anagram hunters. (3) means the name of the game you had to find consisted of 3 words.

The entries with * were special in that they lacked a number (spelled out) instead of a single letter.

elf drama Dreamfall
damaging itch (3) Might and Magic
guard's tale (2) Baldur's Gate
one motto (3) To the Moon
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karate hold (4)* Alone in the Dark (nine)
main stair Sanitarium
ox Nox
rap idiom Primordia
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pools up Populous
fetal thrashing (3) Faster Than Light
only just gone (3)* The Longest Journey (three)
suede (2) Deus Ex
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green fog Geneforge
maniac uncle Unmechanical
reformed King Log (3) Legend of Grimrock
surely forgot (3) Quest for Glory

And yet you still haven't said what it actually was ;)

I updated my post while you were typing that. It was Flatout.

Congrats :) What game was it?

Ah, Flatout, cool.

>___<

Thanks, I would never have guessed that, I was still on the track of thinking that the words meant nothing (even after several trips to wordsmith.org).

Congrats. :)
Flatout was 1st game I won in giveaway here (thanks again Adzeth)

Thanks and +1 for the solution :-)

Wow. just wow...

You're very welcome, drennan! Thanks for spending the time to both solve it and explain it to everyone. I hope you enjoy Flatout as much as I did.

Also, big thanks to anyone who gave the puzzle a whirl, successful or not. I'm happy you did.

I'll offer another puzzle soon.

Nice puzzle! And thanks for the solution! I would never have been able to solve this, actually. I assume perhaps once the mechanism is known, one can throw in a random letter and run anagram and see if anything hits.

Thanks drennan for the solution and grimwerk for the fun puzzle:).