You will need:
• Flashlights
• 3 or more people
• A good sense of direction
• Some woods, or at very least a field with high grass- a cemetery will work because it has things to hide behind, but not many are very glad to let people run around in them at night.You want to do this on a night with very little moom- eg, a very dark night. The flashlights are for safety.
Gather at the edge of the woods, agree what home-base is- It could be the starting point, it could be a big tree, whatever.
This is where it gets tricky- you are inviting something else to be "it". Turn everyone to face the woods and shout in unison: "You're it!"
Everyone splits up and counts out loud down from at most 100, at least 10.
When you get bored or feel like something is after you, run for home-base. Shout "Home free!" or "Olly olly oxen free!" Something to declare that you're running for base.
Most people who play will just have fun running around, or hiding behind things, or running into each other. If conditions are right though, players will become of an extra person at some point of the game, and it may pursue you to home-base. Some may find themselves sharing a hiding place with someone who wasn't originally playing the game, etc.
Take precautions- bring a first aid kit, etc. After all, you're going to be running around in the dark.
Just make sure at the end of the game that you have everyone you started with- no less, no more.
And most of all, don't get tagged.