The base of this effect is an infection system. The infection system uses 3D noise on the first frame of the animation as a resistance multiplier, visualized as green on the mesh, and scattered or rayed points to transfer red on the mesh based on a transfer amount attribute. Once the red reaches the value of 1, the point is tagged as infected, and the current frame is recorded into an attribute. 

The infected mesh is then point deformed back into the animation, and then packed.

The packed geometry is sent into a DOP network, where it gets operated on as a packed rbd object


In the first variation, the packed geometry was scaled every frame after it was tagged as infected. It was then advected by pop wind.

A leading edge of the infection was created by deleting every but the geometry that was infected in the last 5 frames. This leading edge was used to emit particles as well as smoke. The infected attribute was used in rendering for emission.

In the second variation, the packed geometry fed into the rbd solver was tagged as active one it was infected. The active packed geometry inherited the point velocity of the animated geometry. 

The debris and smoke was emitted from the inside surfaces of the rbd cache.