Mounted to the eye is a 10mm blue LED. The head itself is attached to a servo horn and mounted to a micro servo. The head can freely rotate while the eye blink randomly. Surrounding the body are 5mm blue LEDs that illuminate the various surface details.
The random motion of the servo and eye blinks give the illusion of the robot "searching". It's appears quite organic and live like, adding much more dimension to this replica.
Check out the full documentation for this project to build your own. https://learn.adafruit.com/guardian-robot-zelda-botw/
The Fusion 360 source file contains editable solids and micro servo component.