I need a second opinion!
 

Alright, physics system.

I want to make NPCs use an unlaggy physics system.
I was thinking of making it handle the actual changing of their x/y in the clientside and calculating their new x/y every 2 seconds in the serverside and updating it, so players joining the level will see them where they are on others' screens. If that makes sense.

Any opinions on how to do this?