They've matched the motion of the players with a (very rough) 3d version of the player that they are using to drive a 3d liquid/gas/particle simulation. You could do this in Cinema 4D with X-Particles or Turbulence FD. If you have other 3d packages, you could use FumeFX or other things. Heck, you could probably get close with RealFlow and a clever use of shaders.
- The Great Szalam
(The 'Great' stands for 'Not So Great, in fact, Extremely Humble')
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