I really like when samurai and ninja movies do techniques like this because it reminds me of when people back in the day would spread rumors and legends about people.
Some dude in real life probably was not faster than light, but he was trained in swordplay and far faster than the other guy, possibly so fast that nobody could keep up with him. Now we have legends of swordsmen knowing techniques that allow them to move faster than light.
Same with the explosions going off as he jumped away, likely based off legends and exaggerated reports of smoke bombs or fireworks and just evolved into the superpowers we see here.
People back in the day were superstitious and saw magic and gods and monsters in their everyday life, so when we get movies, comics or shows that take place back in the day I love when their powers and abilities can be traced back to something people at the time might've actually believed in.