魔鬼
mó guǐ · HSK 7
devil
👿 魔鬼 = 魔 demon/magic + 鬼 ghost — a magic-ghost is a devil
魔 means demon or dark magic and 鬼 means ghost; stack the two evil-spirit characters and you get 魔鬼, the devil. The mó in 魔 also sounds like the start of monster.
鬼 — head 田 + legs 儿 + 厶
鬼 is a pictograph of a figure with a large, eerie head (田-shape) atop human legs (儿), with 厶 suggesting a swirling or sinister element. It originally depicted a masked spirit or the soul of the dead. The meaning broadened to 'ghost, demon,' and figuratively 'sneaky' or 'clever.'