The interesting thing about this animation is that it's not smooth in the sense of having lots of in-betweens. But what JAMEZ15 is doing here is actually making movements more fast and snappy and making our eyes fill in the blanks to create the illusion of smoothness.
The guy's a legend
wait id say before the floor cracks u should make the person look like he is falling a bit more for example make the body big than shrink it so it will look more realistic fall hope dis helps^^