Circuitmess Wacky Robot Marv Instructions Manual page 26

Now, here's where the magic happens: When you turn Marv on,
the LEDs in the circle will light up one after the other.
Ever wonder how Marv's
decade counter works?
Well, here's how:
If you press the
pushbutton on the
bottom right side, the
LEDs will stop in the
start position (left eye).
On/off
switch