Minecraft wiki entry for Shulker, associated text: The shell of the mob looks similar to a purpur block, blending in relatively easily to its surroundings. Inside the shell of the mob is a small yellow head with two eyes. Shulkers are uncolored by default when using spawn eggs, while white is the default when using /summon or spawners. Spawning shulkers with other colors can be done using the /summon command, as detailed below.