Code game for kid’s birthday party – Gravity Falls

Party Time

My daughter turned 9 this past week and she wanted a Gravity Falls themed birthday party. For some unknown reason, we continue to torture ourselves by hosting the birthday party at our house. At least this gives me the opportunity to make a Gravity Falls-style puzzle game for my birthday girl.

If you haven’t seen Gravity Falls. it’s like X-Files meets Twin Peaks for kids. It’s a great show and is rich with cryptids, mystery, and secret codes. I took it upon myself to make a scavenger hunt/code breaking adventure for my daughter and her friends. It was a bit last-minute thrown together but I think it turned out pretty good.

Threat from Bill

Bill Cypher is the big bad of Gravity Falls. He left a threatening note taped to the outside of the back porch door. I left it there and waited for someone to notice it.

Contained in the envelope was a threat from Bill on a notecard and and other notecard with holes in it.

The kids needed to align the two cards to find the next puzzle. This took some direction as their immediate instinct was to start Googling the solution to the puzzle. Once I put them off of that, they started looking throughout the house for some kind of hint. I had to tell them multiple times they had everything they needed to solve the puzzle. They finally got it.


Cipher Time

Taped to wall of the bathtub behind the shower curtain was the next clue.

There was also the Masonic cypher key along with this. When making the puzzle, my plan was to tie using Google and making the kids find they cypher key themselves. You see, one of the main characters of Gravity Falls is named “Dipper” but that’s his nickname. His real name is “Mason”, which is a bit of trivia my daughter is very proud of knowing. I wanted her to search for a cypher key using “Dipper’s real name” but there were too many variations of the masonic cypher on the internet. I couldn’t risk them getting a different one than I used, so I had to provide the correct key.

Cryptid Hunt

The message says “MONSTERS IN THE BACKYARD”. The five bars at the top represent how many to find. The count of how many to find took them a while to figure out. They had fun hunting in the yard for the figures.

The five cryptids were found. I had to point out Bigfoot, as his brown color and where I placed him made him incredibly difficult to find.

Each cryptid had a letter written on the bottom. They kids had to unscramble the letters and find the word “shell”. A large, pink, conch shell is one of my daughter’s prize possessions, so she knew immediately where to look.


Shell Game

Inside the conch shell was a long strip of paper with a code on each side. One was a seemingly random set of letters, the other side had another Masonic code.

The code says, “USE PAPER TOWEL ROLL”. This was accidentally more difficult than I meant it to be. I didn’t take into account the code can be “read” from any direction! So they had a few false starts on the code. When turning it the right way, a real word appeared and they were off to find a paper towel roll, which I had placed among the party supplies. Of course, at first they overlooked the provided tube and attempted to just unroll a full roll of paper towels to get at the tube 🙂

Finally some smart cookie figured out to wrap the strip around the paper towel roll and the finally code was revealed, “LOOK UNDER THE MAT – YOU WIN”!


The End

Bill had a final note admitting defeat under the back door mat. He was there the whole time!

I have to admit the end was little anti-climatic. The kids already had tons of treats, so I couldn’t think of a good prize to put at the end. While I put all this together pretty last minute, the kids really enjoyed the hunt. It was a nice break to get the kids to stop eating candy, get outside, and use their smarts.



Great stuff! Looking forward to pulling one of these off in the future.


What a great idea! My son wants a Gravity Falls party for his seventh birthday at the end of the month, so I’m trying to plan some fun activities 🙂


Dear Brad! My daughter turned 9 this year and wanted a Gravity Falls theme party to celebrate her birthday. I was looking for a game puzzle to entertain the kids (yeas we also are hosting parties at home…) when I found your blog with this great game! As I don’t have all this creativity, I copied the game you did just adapting to our house and to our country – Brazil. I must tell you that the game was a hit and the kids had lots of fun! Thank you so much for sharing it with us and congratulations for the fun game you have put together!


I’m glad you enjoyed it 🙂

I did another puzzle game for my daughter this year too but it was Yo-kai Watch themed. I need to document it and post it.


Hi! I borrowed your game idea and it was a hit for my daughter’s 12th bday. They all had a blast trying to think and decipher, loved it!!! The prize was a trophy with a Mystery Shack tag on it!!

Thanks for your post and sending you huge hugs!!!


I’m glad they enjoyed it! 🙂


Love this! Thank you so much for sharing! Can you please tell me where you found the little plastic monsters?


I just ordered the little monsters off of Amazon.


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