This is a great sleepover/summer party game. You can play this with 4-10 people.

This isSIMILAR to manhunt. The key word there is SIMILAR. Not the same thing except with ninjas.

Anyway, this gam may need some pre-planning, so make sure there is time to explain rules.

Step 1: Set Up

The minority of players are ninjas. 1/4, 1/5, 2/6, 2/7, 3/8, 3/9, and 4/10 players are ninjas. The other half are guards. Play during nighttime. The house is the base. Inside at the top floor of the house, put a briefcase labeled (TOP SECRET). Put a guard to each door in your house outside. Make sure the doors are unlocked. Put the rest of the guards in each room, spread thin, with one upstairs guarding the briefcase.

Step 2: Equipment Needed

The equipment you need is very simple, so I'll just make a list.

A bokken, or boffer katana. Can be purchase online one the true swords website:

http://www.trueswords.com/ , or made using this instructible by ES16: https://www.instructables.com/id/PVC-Training-Sword...

Origami shurikens. Look up any tutorial online. Make 3 for every ninja. Use construction paper.
All black cloths. Ask guests to wear all black cloths. Ninja hoods optional.
iPhones, or other smart devices. Set up as cameras wherever there are guards. You can use iMovie to splice the videos together and make a movie.
Nerf Guns.(Optional) Give them to the guards. I personally think this is overpowered but it's a free country.

Step 3: Rules for Ninja

Give the ninjas all black clothing, a bokken sword, and some shurikens.

The goal for the ninja(s) is to infiltrate the house, get to the briefcase, and leave without dieing. They must start in the woods, and must enter the home from there. If they are seen, it doesn't matter. The guard CAN call other guards, but he most likely will fight the ninja.

If the ninjas get to the briefcase, take it, and go back into the woods, they win, but they also have the choice to kill all the guards.

Step 4: Rules for Guards

The guards are the only people keeping the briefcase safe. They must walk in special patterns and must squint and wear earplugs. Otherwise the game is to hard. If they see the ninja, they can fight and yell for guards. But if they are killed, they must fall down dead and not make noise. They win if all ninjas are killed.

Step 5: Combat Rules

When combat is engaged, they fighters must use their swords only. Shurikens are only for unaware targets. After a shuriken is used, there is no picking it up. To make the combat as safe as possible these are some valid points of attack.

Body strikes are the only kills. Strikes to arms and legs do not count at all, so there is no argument. Head strikes are illegal, and the offenders automatically die if the strike someone there. The sake rule goes for groin shots. In between blows, the ninjas can kick, but only to the chest. But BE GENTLE. You are attacking another human being. If you are killed, you must lay their until the round is over. NO TALKING WHILE YOU ARE DEAD!

Step 6: Optional Stuff

You can use the video camera idea. It is pretty cool to watch.

Here are some optional "Modes"

HARDMODE: Only one ninja. Every strike counts as a kill. No shurikens. Guards don't have to squint or where earplugs. And there are no patterns to walk.

SPY MODE: Ninja/Spy uses a one shot nerf gun with reloads. Guards use other guns. Fist fighting. Sword rules apply, except three strikes to kill. Tap red yarn from one wall to the other to simulate laser traps. Play during day.

HITMAN MODE: Instead of a briefcase, you have to kill a person.