It’s a multilayer font so every group consists of 4 fonts – Regular, Back, Front, and 3rd Color. The Regular style is for single color use only and the Back, Front, and 3rd Color styles are necessary if you want to achieve a multicolor effect.

Position three identical text boxes exactly on top of each other, apply layer font styles, and choose whatever colors you like. You’ll quickly discover that some icons don’t have 3rd Color style. This is not a mistake – a lot of things look good with just two colors.