If you’re going to dress like Gambit from the X-Men, you may as well put in the extra effort to replicate his signature cards. Instructables user yota came up with a design to mimic the glowing cards using plexiglas, red LED, 3v lithium battery, 100 ohm resistor, wire, a momentary switch, and hot glue. She sketched the card design onto cardstock and incorporated the X-Men logo and referenced Xavier’s school but mentions you could also just cut up old playing cards – you’ll need two of them. Solder together the electrical parts and cut the plexiglas to the shape of the card:
Cut your plexiglas. It’s a pain in the butt to do, but you can use either a jewelry saw (slow!) or a dremel tool (inaccurate!). I used a dremel, because I’m impatient. Plus, you’ll need one for etching in those grooves for your wires and drilling any holes. When cutting, if you can’t be completely accurate, better to have the piece be a bit too big than it be smaller than your cardstock cards.
Adding the wires to the plexiglas:
Stick the wires in the grooves and keep them there with hot glue. Then go over the whole bloody thing with a thing layer of hot glue to diffuse the LED, but don’t go over the area of the spade design (you’ll ruin it!).
Read more and see more photos of the build at Instructables.