When I was playing dying light with friend we discovered that every timw you go to sleep and wake up air drop will appear, if you don’t know air drops are pretty rare and if you collext them and deliver to one guy you will recieve lots of xp, we used that multiple times to unlock grapling hook very early. Air drops also gave lots of medicine which was hard to get in early game and that very helped us
GTA online car dupe glitch. I used it nonstop before it was eventually patched. I own everything I could want in the game and still have a ton of garages full of cars to sell.
Also, the gold bar glitch in RDR2 that allowed you to just keep picking up the same gold bar indefinitely. I tapped down the button on my controller and just let it run all day.