Reader Discussion: What's The Hardest Puzzle You've Ever Solved In A Game?

I'm playing through The Witness right now. I'm really bad at The Witness. I do have little moments of triumphant though, where I finally click together the pieces in my mind and solve a puzzle that's been giving me trouble for an hour. It's a brief, fleeting sense of victory quickly swallowed up by the realization that i have hundreds of puzzles to go.

Ah well.

Let's talk about puzzles in games. What are some of the hardest ones you've solved? The ones that forced you to beat your head against a block for hours until the solution popped in your brain? For me, it's the babel fish puzzle from the Hitchhiker's Guide To The Galaxy text adventure (yes, that's a thing that exists). The babel fish puzzle isn't really that different from any other weird puzzle in early adventure games except if you don't solve the puzzle the game becomes unwinnable. Yup. Finding this out when you're a nine year old kid suckssssssss. Eventually I got through it without a guide...on my fourth attempt...with my dad's help (still counts).

What about you all? What video game puzzles have given you the hardest time?