The Circuit Playground Express has a built in infrared (IR) transmitter and receiver. With a pair of Circuit Playground Express boards, you can send and receive messages that will cause the boards to run prepared operations. In this case, being "hit" with an IR blast causes the NeoPixels to count up from one to ten shots, and then score the final hit with an all red light fill and sound effect!
Play laser tag with a friend, or use it for target shooting. Too easy? You can also make it more of a challenge by adding a straw or empty pen barrel to cover the transmitter (TX) IR LED, thus narrowing it's cone of light.
Here's all you'll need: