Hidden Blade: Main Project Inspiration

For my main project, I am thinking about doing a hidden blade; inspired by the videogame saga Assassin’s Creed. In the videogame series, the hidden blade is a concealable weapon that undergoes many aesthetic and functional variations. The first hidden blades showed in the game are owned by Altair and the other Assassins, they are based on a primitive model since it requires a flick of the wrist to extend and required its user to cut off their ring finger to allow the blade to extend. This was based on both a traditional rite of passage and a requirement to use the blade.

Altair featuring his hidden blade
Hidden Blade Configurations by Damage-Inc

In Assassins Creed II, the hidden blade was modified by Leonardo Da Vinci and adopted a new mechanism that didn’t require the users to cut their fingers off. Many more functional modifications with added features were seen throughout the games. Additionally, the aesthetics of each gauntlet holding the hidden blade matches the aesthetics of the era and region in which they were used.

Most of the hidden blades feature a resemblance to the Assassins’ crest as part of the bracer’s ornamentation or design; these bracers are made of materials such as leather and metals with carvings and jewels to decorate them.

Hidden Blade Schematics
Assassin’s Crest from ABYSTYLE originally from the videogame Assassin’s Creed

From the many variations on aesthetics and functionality, the hidden blade retains the main feature, its blade can extend based on something the user does and retract after the user does something else. I tried making my own hidden blade when the first games came out (in 2008), I used a ball bearing roller slide that I got from Home Depot with a letter opener to make the hidden blade. To activate the mechanism, I used a ring attached to the roller slide with a cable. A couple of springs retained the tension in the mechanism such that when the ring and cable were pulled the blade extended and when tension from the ring was released, the blade retracted. The final result achieved the desired main goal of a hidden blade, but the performance standards were not up to my expectations. The ring and cable had to be pulled significantly far to achieve the desired blade extension, therefore, my hand had to flex pretty far back. Back then, I based my design on a YouTube video showing how to make a hidden blade. Nowadays, there are many YouTube tutorial videos available and I believe that with my engineering skills I can build one with better functionality and a more modern aesthetic than most of the other ones out there.

AC Modern Hidden Blade by Zafictus888 on @DeviantArt

For my new design, I plan to use a motorized mechanism with a rack and pinion to extend and retract the blade. I also plan to give it a modern aesthetic instead of the videogame’s medieval or renaissance styles. However, I do plan to incorporate a good amount of ornamentation and obviously, the Assassin’s Crest.

Here is a video of what I consider my competition to look like:


Image Sources




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2 Comments. Leave new

  • Cool Idea Gary! Hidden retractable blades are pretty cool, and I guess in a pinch, might prove pretty helpful. Playing on the Aesthetics of Assassin’s Creed is also a great idea, and i’m sure with your love of the game, you will have no problem creating a product that stays true to the vibe. I have a similar question to Ben, but I’ll pose it differently. If you intend to use a real balde for your project, how will you ensure that it is both safe and legal?

  • Hey Gary,

    I think this is a really cool design for the final project. I love how you gained inspiration from a video game you enjoy. I’ve never played Assassin’s creed but I’ve watched my roommates play. The retractable knife makes me think of the movie Taxi Driver where the main character makes a retractable gun. What are you planning on using for the blade? Is it going to be functional and sharp or just ornamental?


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