The schematic as shown on the “Hardware” page (and in the Ooze Master 3000) guide presume that everything will be powered through the Feather board’s USB port.

With the number of NeoPixels we’re using, and running the code as it’s written, this is all fine and good.

However, quite often a thing occurs with NeoPixels. One moment you’re animating a few pixels with a carefully planned formula…the next, you want way more pixels, all simultaneously lit in different colors and synchronized to Christmas tracks by Mannheim Steamroller. NeoPXL8 can handle all that data, but a USB power supply can’t feed that much current.

I can’t help with the Mannheim Steamroller part, but the power issue is pretty straightforward…you just need to power the Feather board (with NeoPXL8 wing) separate from the NeoPixels, with a ground wire linking the two:

Use a regulated 5V DC power supply for the NeoPixels, whatever capacity meets your needs…we have many to choose from, up to 10 Amps, and these handy screw terminal block adapters as well.

You don’t need to do this if building the project as described. This is only if you find yourself taking things to the next level!

Deeper insight into NeoPixel power consumption can be found in the Adafruit NeoPixel Überguide, NeoPixel Curtain project and Sipping Power with NeoPixels.