This page contains the nitty-gritty trials and tribulations of developing the SCP-1471-A MalO Simple Add-On (SAO). These units can be pre-ordered online and picked up at DEFCON34 in August 2026.
As part of the standard DEFCON experience, each attendee receives a circuit board they wear around their neck that serves both as a multi-day ticket for the conference and as a platform to show off hardware/software hacks. These MalO SAOs plug into the expansion port on the official conference badge to allow the user to customize their standard DEFCON badge.
Among other things, these MalO units have a screen, LEDs and buttons to allow the user to play games, unlock puzzles, display screen savers, view messages, etc. The devices can communicate with one another over infrared and Near Field Communication. The units have a USB port where users can hack them with Python.
The idea for this project came together while walking around Supercon 2025 and combining several factors:
- I made made an SAO design for DEFCON31. I had a base design that could be customized with a sticker. One lesson learned was that scrounging through a bag to find the exact right sticker the customer wanted was time-consuming. Rather than many products offered at a single price point, it's better to diversify the product offering across price points, or just offer a single configuration of the product. Also, the dark/broody design sold the best (and incidentally was the one I made the least copies of and sold out first).
- DEFCON is themed around skulls and hacking
- If centering the design around a character, it would be advantageous to avoid copyright (ie. open source character), but still have something recognizable. This being for DEFCON34, could have a tie in with rule34... (but still keep the hardware and software design formally SFW)
- A rock-paper-scissors type interaction is very effective as an ice breaker, but lacks motivation to continue talking with the person after the first interaction. Want something with more staying power, like a chat bot that is broadcasting messages/replies - so the longer you talk with someone (assuming both have this SAO), the more of their messages you pickup, and maybe unlock perks in the SAO... (FYI, laser tag has been done)
- Have had requests in the past to make the SAO hackable, so want something modern running at least some Python, so thinking RP2040 or ESP32 product line for good community support. Went with RP2350B and 16MB external Flash.
- I've had trouble conveying information (game/menu state) to users with LEDs alone, so want to include a proper screen in this design so information is all presented in one place.
- I wanted to do capacitive touch buttons since they are the lowest profile option and feel better (imho) than traditional clicky buttons. ESP32 has a built-in controller for this, but the RP2 series does not. So doing capacitive touch on the RP2 series will be a gamble/risk... Since most are right handed, would have the buttons on the right, and the screen to the left.