We have all heard of some of these, if not played one of them. There is a lot of risk in them, even though you might think they're just a fun game. You are summoning demons and spirits or trying to go to other worlds.
One of the most famous games is Bloody Mary. If you haven't heard of it, the premise is simple: You go into a dark room with a mirror, then you say her name three times. In some versions you have to turn around and have a candle. She will appear all bloody then if you say, "Bloody Mary, I stole your baby" three times, she will scratch your face. You are more likely to see something if you you're kid.
Next, one man hide and seek originated from Japan and was originally called Hitori Kakurenbo. It's where you play hide and seek with a doll. What you will need is a doll that has stuffing at least in its torso, a red thread, scissors, a needle, a bathtub, rice, nail clippers, salt water, incense (or sage), and a hiding place. What you do is you open the doll and take out the stuffing, then clip your nail, putting the clipping into the doll. You also put the rice uncooked into the doll and sew it back up. Then you fill the tub with water while you name your doll and you purify the room with the incense or sage. After you do that you say, "(your doll's name) is first" three times and submerge the doll in the water. You have to then turn off the lights and hide with something sharp. Count to 10, go to the tub, and say "I have found you, (your doll's name)." You have to open the doll and tell it to find you, then go back to your hiding place. You fill up your mouth with salt water (don't swallow), and then go find the doll. You then spill the rest of the water onto the doll saying, "I win" three times and finally, you then burn the doll.
Lastly, the midnight game is based a pagan ritual where you summon a spirit called the midnight man. In the pagan version, this was a punishment to do this ritual. What you need is salt, a candle, a pen, something to light the candle with, something sharp, and a piece of paper. What you do is write your name on the paper, then poke yourself with the sharp object, and put a drop of blood on the paper. Light the candle and turn off the lights. Put the candle and the paper on a door and knock 22 times. The time must be midnight on the final knock. After you are done knocking, open the door and blow out the candle, then close the door again. Relight the candle and you have started the ritual. Walk around and try to avoid the midnight man. You may see a human-like figure near you or hear whispers. If the candle goes out, relight it in 10 seconds, or if you don't, surround yourself with salt. This ends at 3:33 AM, and if you can't avoid the midnight man then he will remove your organs or send you to another realm.