Providing the player with new tools or adjusting the game interface, without fundamentally changing gameplay.
Change the color of the player depending on a circuit condition. By Using the red, green and blue wire signals you can change the color of your Engineer by selecting the output of a combinator. The output signal will be interpreted as a 8-bit RGB value and control the Engineers color which is updated every few game ticks.
Providing the player with new tools or adjusting the game interface, without fundamentally changing gameplay.