a common side effect of smoking high quality marijuana. the main symptom is loss of body control, which the brain interprets as muscle paralysis or muscle stiffening. there are two known cures: a body part must be moved/touched/pushed by an outside force, or mentally overcoming the effect with meditation.
Carl: Dude this is good weed.
Greg: I know, I can't move.
Carl: You got the Rigor Mortis!
Greg: Dude, touch me. I'm stuck!
Carl: Haha no I'm gonna go upstairs and steal your parents' personal items.