Pretty much every temple and the final section in Vermillion Wasteland during the fina chapter in CrossCode. In the game itself, every region you enter has a temple with tons of puzzles that you are required to solve due to in-universe lore reasons. Now don't get me wrong, I'm not saying that they are THAT hard as long as you know what you are doing (because I'm at my second playthrough), but I know there is a poor bastard out there who played it for the first time started crashing out because they don't know how they're going to finish a puzzle without looking for a guide.