The puzzle game Fez was first released in 2012. The player character exists in a two-dimensional world, but when he is gifted the titular fez hat, he is able to rotate through the third dimension to access hidden paths. In doing so, he collects three-dimensional objects.
Many of the puzzles are quite difficult, but invariably can be solved by astute players who carefully observe the details of the game and think outside the box. Some of the puzzles require tapping controls in the right sequence, making the hidden objects materialize for collection. However, since the game was released nearly fourteen years ago, one puzzle was never solved. Players were only able to collect the final object through brute force. They figured out the correct button sequence to tap in, but no one has ever been able to find the in-game process for finding the solution. After enough time passed, players accepted that the solution was simply absent from the game. The brute-force ‘solution’ was the solution.
I return to Fez every few years, just long enough that I forget the exact method of solving some of the tougher puzzles, which keeps the game engaging. I began my most recent playthrough a few days ago, and caught up to the unsolvable puzzle. The first half is accessible in-game. A certain item, collected much earlier, instructs the player to stand in a certain location and tap in a button sequence. This summons the Black Monolith. The second half to this puzzle is the part missing from the game, so I typed in a search online, and was taken to a Reddit thread posted ten days ago.
Ten days ago, someone (username stone_von_holy_bless) shared that they had finally discovered the in-game solution. Providing extensive notes on their thought process, the end result demonstrates just how unintuitive the proper solution was, explaining why players have missed it for so long. Players have to stand in several different locations and pay attention to a variety of obscure background details—including one found only on menu screens—and must realize those details are, in fact, the sequence of buttons which must be tapped back in the Monolith room.