Introduction: Cardboard Fortress Battle! (capture the Flag)

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Hold thine cardboard horses, and raise thouest cardboard tubes, because ye have been called upon for delightful papery battle! When you mix forts, cardboard, and capture the flag, you're sure to get something great! Whether you're a full-on LARPer or allergic to the idea of going to a Medieval Times restaurant, you'll still enjoy this a bunch. Time to lay siege to your recycling bins, and get ready to add some glory to your weekend.

  • What: Cardboard Battle! (capture the flag)
  • Time: ~ 2 hours to set-up, joy forever
  • Concepts: Happiness, teamwork
  • Materials:
    • Cardboard Tubes
    • Cardboard Boxes
    • Cardboard sheets
    • 4-6 rolls masking tape (for forts)
    • Duct Tape (for sword and shield)
    • 2 flags (pieces of fabric)
    • Decorating supply (markers, doilies, stickers)
  • Tools:
    • Cardboard Cutting Tool (X-acto, lasers, scissors, or boxcutter)
    • Jambox (for epic music)

This game is greatly inspired by the game "Ultimate Team Cardboard Fortress Battle" by Jon Sung, who is just a delightful and brilliant man.


Step 1: Assemble the Cardboard Hoard

Time to get out collecting! You'll need tubes for swords, boxes (for forts), and if you want, sheets for the sword handle and shield. You can also cut these out of boxes you find in the recycling. You can find tubes at many crafting store recycling bins, and boxes in most commercial areas. A great way to bring cardboard boxes is to have everyone bring a couple that they find on their own. You're hoping for about 30-50 boxes total.

Happy hunting!

Step 2: Shields and Sword Handles

Measure your tubes to see how wide they are, and make a handle with a hole accordingly. I made designs for shields and sword handles and cut them out on a laser cutter, but you can do this by hand too, no problem! I made about 40 sword handles and shields for the day.

Step 3: Load Up!

Throw all that stuff in a car along with some markers, flags, tape, and a boombox, and you're ready to go find your friends!

Step 4: Forging Swords

No sweat! Just slide the handle on the cardboard tube, and give a little duct tape to secure it in place. I found that for the game, a sword about 18" long is great. Decorate it up, too!

Step 5: Smithing Shields

Making a shield is a wee more tricky than swords, but not bad. Make two handles on the back, each with two pieces of duct tape stuck front to front. Tape them down at either side, and you've got yourself a shield! Of course, it will be your coat of arms on the front that will protect you, so decorate that too!

Step 6: Rules of Engagement

So while it's super fun to just whack each other with cardboard, here are some rules as a framework for how to whack each other with cardboard and steal some flags in the process.

The Rules


  • There are two teams. They should decorate selves, swords, and shields according to team theme or color.
  • They should elect a general of their team.

The Forts:

  • Divide the cardboard boxes evenly among the two teams. Each team gets five minutes to build a cardboard fort using only those boxes and masking tape.
  • Forts should be about 75 feet away from each other.
  • Each team should hide their flag somewhere in their fort.


  • After forts have been built, generals will each give a motivating and epic speech.
  • Game begins, and first team to grab the other team's flag in hand and return to their fort wins.
  • If you get hit in a limb by a sword, you lose that limb. If you get hit a second time, you're out. Body shots get you out immediately. Head shots are illegal. Keep it safe!
  • If you get out, go over to a pre-set area, where you have to count to 100 as fast as you want in your head before you're back in. Then you're back in!

That's about it. For the details, feel free to make up your own!

These rules are largely based on Jon Sung's game, "Ultimate Team Cardboard Fortress Battle," and he has a great write-up so you should check that out, too!

Step 7: Building the Fortresses

As stated in the rules, each team gets five minutes to build their forts with the flag somewhere inside. They can only use masking tape, and can't "mummify" as box, meaning fully covered in tape. Don't worry about them too much, as these will get decimated soon.

Step 8: Speeches From Generals

Every battle needs some epic speeches. Have each general give an inspirational speech before the two lines run at each other.

Step 9: Battle for Honor!

Oh, the epicness of it all. See the rules for engagement, but basically you have two teams trying to destroy each other's forts looking for the flag. If you get sword-ed, then you're out for a wee bit, before you get to re-enter! To re-enter, you can make people count to a number or do something silly. They had to read academic papers aloud here.

Step 10: Find That Flag! (and the Aftermath)

The first team to find a flag and return to base winds! And then you all can collapse into a heap on your lovely new cardboard mattress. At the end, either re-build and re-match, keep your new knightly wares, or return them to the recycling from whence they came.

Have fun, ye cardboarded knights!

Thank you to Eda for so many of the action photos. :)