First, it reminded me of the Beastmaster Hero's Ultimate from Warcraft 3 Frozen Throne, the rampaging lizards
Second, Mei actually PRONOUNCED THE WORDS CORRECTLY instead of using varying pitches of tones to replace them.
Next time he can just lay down on his back to begin with, problem solved assuming they can't roll around like a restless sleeper and end up face down anyway... but if they can do that, they'll just unconsciously move around again if needed anyway.