Variants of a mold are catalogued separately, so each one has its own sets and minifigs. Check these too if something you expect is missing here.

• 19727pr0003 Minifig Head Special, Cube with Rear Ledge, Pixelated Light and 1 Dark Bluish Gray and Black Face Print (Mooshroom) this part is a alternate of it
• 19727 Minifig Head Special, Cube with Rear Ledge [Plain] this part is a print of it