What is a video game mechanic that you didnt know about until you were about 90% finished with the game?

1. Spoilers for Dragon's Dogma. There's a reputation system in Dragon's Dogma that determines how much each NPC likes you based on how many times you've talked to them, how many items you've given them, and how many quests you've done for them. It doesn't seem to affect much except for a few lines of dialogue and maybe shop prices. That is, until you hit a point in the main storyline where whatever NPC likes you the most gets kidnapped. As soon as you beat the bad guy and rescue that NPC, your character and the NPC start furiously making out. Turns out it was a romance system the whole time! A bafflingly poorly implemented romance system. Also, the NPC the game picked to be my surprise lover was a magical being who has the appearance of a prepubescent girl. My character was a woman. It's not often you get hit with the revelation that you've been playing as a lesbian pedophile the whole game.
   — PopeHatSkeleton


2. In some pre-release article or video about Bioshock Infinite, it was mentioned that using tears would cause permanent accumulating damage to Elizabeth, so I went my entire playthrough activating them once or twice. Only after I finished did I realize that they removed the penalty and I could have been summoning items/weapons/etc at will.
   — tenaciousod


3. Not me but a friend of mine played red dead redemption with a bandana on because it looked cool. When he watched me play on my save game he suddenly realized he never got any honor or fame because of it. By then he almost finished the game.
   — Talazarius






4. In Fallout 3, I didn't know you could hold down the button to continuously drink water. I thought you just had to keep tapping the button and letting your character take one sip at a time. EDIT: I feel so much better knowing I'm not the only person who completely missed this for the longest time.
   — apocalypticradish


5. I didn't know Windows Mineweeper had optional sound effects until I had been playing it for twenty years.
   — lobster_conspiracy


6. Most recent for me was getting to the end of subnautica without finding the prawn suit blueprints. Would've made some things a lot easier.
   — alexthegreatmc






7. I somehow played through 3 in-game years of Stardew Valley before realizing you could expand the range of your watering/digging tool
   — TheLastSpoonBender


8. In Fallout 4 you can pickpocket the fusion core out of power armor an enemy is using and it will eject them from the suit.
   — Blockwork_Orange


9. I didn't know about the carts in Skyrim until I had finished the main quest and been to every hold. That being said, not being aware of them led to some really cool moments like making my way up the eastern coast to Winterhold during a blizzard and fighting an ice troll in the glacier on the way. Edit because everyone’s asking: near each major city (generally once you’re outside the gates and have gone down whatever entry ramp or bridge is there) there’s a guy with a horse drawn cart. Talk to him and he’ll fast travel you to any hold capital for some gold.
   — Elcactus






10. In Borderlands 1, I picked up each item one by one until the end of the game, where I discovered that a long press on the action key would pick up all the money and useful ammunition on the whole zone.
    — ManthBleue


11. Camping to fast travel in Red Dead. I probably overlooked it because I didn't use fast travel once my first play through so I wouldn't have used the camp one anyway, but I had no idea you could save or fast travel any time.
    — Jordanlf3208


12. Mass Effect, the first one. Spent the whole game without knowing the Mako had a cannon (and a pretty effective one at that). I spent the whole game using only the machine gun, thinking how stupid it was that this tank did not came equipped with a better weapon. Started another game, trying to be an evil Sheppard. I accidentally press the right shoulder button. Boom. "Oooooh... I’m an idiot." Also took a while to discover you could also use a scope / zoom in feature with the cannon.
    — HopeImSane






13. Not me, but when my wife was a kid, she and her sister would play Kirby on the NES. But they could never beat King Dedede at the end. Years and years later, we were playing some Kirby (probably on Wii) and she was amazed that I could make Kirby swing a sword, shoot fire, etc. Turns out they never learned how to steal powers and just ate the enemies and spit them out for attacks.
    — kingfisher_42


14. You could upgrade your weapons in resident evil 4. Beat the whole game when I was 11 and didn’t figure out you could upgrade weapons til I replayed it when I was 16.
    — SubSonicFrog


15. Hitting an enemy with a torch in Skyrim sets them on fire. I didn't know this until Survival Mode from the creation club was released (6 years after the game was released).
    — DoctorSneak