In my playthrough of Big Walk, I found the "heavy golf ball flag" puzzle early on, but my walking buddy and I decided to leave it for later and used the gourd to complete the Blue Tower. However, some players might come across this earlier and use the gourd for a different tower.
We had no idea how to complete the puzzle, but once you figure out how to solve it, you might end up feeling a bit dumb (just like we did!)
TL;DR: In order to "move" the heavy ball, you'll need the help of a friend. One person just needs to pick it up, and then another player has to grab it from them. You just rinse and repeat until the ball ends up at the top of the hill and is dropped into the slot by the red flag.
What to Do With the Heavy Golf Ball in Big Walk
Not too far from where the heavy ball is found, you'll see a hill leading up to a red flag and a locked red gourd. To unlock the gourd, you and a friend will need to work together to get the ball up the hill.
It'll take a couple of minutes, but one person needs to grab the ball, then a second player needs to grab it from their hands, and then the other player needs to do the same thing until you walk up the hill together. You don't need more than two players to solve this puzzle (or any puzzle in Big Walk for that matter), but it might take a bit longer.
It's worth noting that this is not the only heavy ball/flag puzzle in Big Walk. There's one later on that you can complete to get a purple gourd, which is needed if you want to unlock the game's true second ending. This one is a bit harder, though, because you will essentially need to transport a heavy ball across the map using the train and the ski lift. It's not required to complete the main ending, though.







