Continuity mistake: Wick takes the lapel pin off and places it in his right front jacket pocket. Shortly afterwards he takes it out of his front left jacket pocket. (00:49:10 - 00:56:20)
Continuity mistake: During the fight at Osaka Continental between John and Caine, a knife lands near a display case corner. However, when the shot changes, the knife disappears.
Answer: These are dragon's breath shotgun shells. The shells are filled with magnesium pellets and ignite when fired. The film seems to exaggerate the stopping power, making it seem almost like an explosive round rather than incendiary. These are not the same rounds that we see the men carving into. Carving grooves into a bullet is done so the bullet expands upon impact and causes more damage similar to a hollow-point round, though the effectiveness of this method is debated.
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