particle woes - effectors/multiple collisions

I´ve ran into some problems and not yet found a solution.

I want particles, that on collision die, and create 2 new particles, where those 2 on collision die again and create another 2 particles each. With a limited iteration amount.

Goal is, maybe someone got another idea how to do it, to smash a stone with size 1 into a metalplate and kill it, and then emit 2 stones with the size 0.5 each and so on, maybe 4 or 5 iterations.
And one stone should become many. I´d like to do it with board instruments if possible, not start to code my own python phyisics simulator though =)

Another problem is, that making an collision effector on a Particle System only triggers once, is it not possible to let one particle collide several times and emit new particles on every collision?

Anyone?

Maybe someone also could point to a tutorial explaining the “Target Object / Target Particle System” option for Particle emitters, as I haven´t exactly been sucessfull yet finding any.

tia.

Found out about that one.

Create object1 with emit1
Create object2 with collision and react1
Set object2 to emit on collision from face NOT particle, multiple and target object1:emit1

Was not aware of the fact that the face emits from where the collision took place, so i desperately tried to make multiple collisions on the particles in the first place :smiley: