crawl
Marks the NPC as moved with the crawl movement type. If more than one crawl/walks are sent in one cycle, it will instead be treated as run. If more than two crawl/walks are sent in one cycle, it will be treated as a teleport.
Parameters
delta
the x coordinate delta that the NPC moved.
delta
the z coordinate delta that the npc moved.
Throws
if either of the deltas is not in range of -1..1, or both are 0s.