This color scheme variant is Monochromatic. I used shades of light blue ranging from almost near white to a dull grey blue. Only four shades were used. The reason I picked these colors is because it is a Sci-Fi themed game I wanted some neon like colors.

This color scheme variant is Analogous.  I used shades of blue ranging from dark blue to blue green. Only four shades of color were used . I wanted blue to be the main color since it is a sci-fi themed game.

This color scheme variant is Complementary. The colors used were Blue and a gold orange. I used this since both are sci-fi related colors since it is a sci-fi themed game. I only used two colors for this sketch.