pattern is printed and glued to a board - in this case scrap flooring chipboard
target areas are neoprene (bits of old wet suit) covered with lame material and glued and stapled to the board. Wrapping around edges of the board means that sabre cuts can be used and monitored
Arduino code is similar to MKII, but with a fifth target,
circuit - for the LEDs it's simpler and cheaper to have one resistor on the ground lead, rather one per LED