Date: Always October 31
Time: 6:00 p.m. - 12:00 a.m.
On October 31st Jack will visit beginning at 6:00 p.m. Boo! As soon as you start playing empty your pockets to protect your items from tricks. Empty your letters and gather candy but put the candy in your letters, not your pockets.
Wander around with empty pockets trying to find Jack who has a pumpkin on his head. Beware that all the villagers will be dressed just like him. They will turn anything you have in your pockets to Jack-in-the-Boxes without your consent. They will irritate you and waste your time. If you don’t have anything to give them they will turn your head into a pumpkin and give you a yucky shirt. The way you can tell them apart from Jack is that they will approach you, in fact they will chase you and talk to you even if you don’t click “A.” If you get kind of close to them and they turn their head to look at you, it’s not Jack. Run away. If you get caught don’t worry as long as your pockets are empty.
When you find Jack he will walk around but not follow you. Some say he looks a little taller. Walk right up to him but don’t talk yet. Take one candy out of your letters and then press “A” to talk to him. He’ll have a little conversation and ask if you will “grease his palm” with candy. Choose the option to give him the candy and he will proceed to give you something from the Spooky Set. Problem is, it will be random, and he will give you doubles, but not everything you want.
As soon as Jack gives you an item, open your pockets immediately. This will prevent an animal coming along and turning your item into a Jack-in-the-Box. Now put the item you just got into the letter you just took the candy out of. The Spooky item is now safe.
Continue giving candy until you have all the Spooky items you want or you run out of candy. It is likely that you won’t get the whole set unless you stockpiled a lot of candy. In this case your only option to complete the Spooky set is to trade with other people.
How do you get your items out of your letters without it being stolen from the villagers? Go to your house and take them out of your letters and put them in your house. Wait until Halloween is over to safely go outside with any items in your pockets.
"During Halloween, all the neighbors asked me for some candy, if you didn't give it to them, they give you a pumpkin head. If you don't give it to Jack, you get a Pumpkin head (1st time), Moldy Shirt (2nd time) and Jack-in-the-lantern (3rd time). Jack expects Candy when he sees you, he writes you a letter early in October, to give you notice. Nook sells candy October 1-October 31st but only 1 per day so you can only have a maximum of 31 per day. I wasn't able to try out giving candy to the neighbors because I didn't have enough. Jack disappears each time you talk to him, so often you have to walk around the town to find where he is. It's kinda hard to tell him apart from other trick-or-treaters because they all wear the same outfits. I think Jack is slightly taller."
We haven't played this holiday yet (in City Folk), so we are extremely thankful to Brianna for finding out this information!