Green’s Dictionary of Slang

(US) to beat, to injure, to damage.

1924		D. Hammett ‘Nightmare Town’ in Nightmare Town (2001) 12: Some day we’re going to find him all momicked up.
1934		Z.N. Hurston Jonah’s Gourd Vine (1995) 46: Is you heard who took and scratched it, and put smut out de chimbley all over it and mommucked it all up?