Not all that impressive for a game today, but this was basically unheard of in the 1980s and it explains how the movements were so smooth.
If you’ve played it a decent amount of times, you will recognize every movement in the live action video as it looks in the game.
Also, for those who don’t know what rotoscoping is: https://en.wikipedia.org/wiki/Rotoscoping
IMHO it was the two things, rotoscoping and good animation, there’s other games that used rotoscoping and they don’t have the same smooth movements.
Other game where they got awesome results is Another World.
I forgot all about that game! It was incredible! Just nothing like it at the time.