How much new stuff do you want to learn for this? How are you with assorted crafting skills?
If you want to level up, make it out of acrylic with LEDs.
There's a pretty recent tutorial on Adafruit for doing something similar. The tutorial has a fully programmed circuit board for animated lights, but you wouldn't need to go that far for this project - just a simple on/off battery pack hidden in the shirt sleeve would be enough.
For the runes, mask off the non-glowing part with tape, and use sandpaper to sand/frost the part that should glow. The sanding/etching in the surface of the acrylic will catch and diffuse the lights.
(you might need to make a free account on Adafruit to see it)