p8guitar wrote:But what would be a clever way to create a pile of this symbols at the ground?
first you have to decide what that pile would look like and how it would swamp the protesters. would it be a fixed heap of solid things, or maybe the "coins" on the top of the heap might bounce around or be moved by characters, or would it be like a fluid? when you've decided that we can go into details - but in principle one way to do it (and I'm sure there'll be other suggestions too):
the water cannon particle duration is set so that they disappear where the heap / liquid is..draw the whole final heap, decide how the top edge will appear - waves / pyramid / ... and put it into a masking group, then move a mask to reveal more and more of the heap
to make coins appear to splash / bounce off the top - have another particle layer - animated origin - that spits coins upwards that then fall back to the surface under the influence of gravity
to give the characters control of coins you could animate them throwing individual coins or have several particle layers that each track an arm movement, that you turn on and off, and that spit coins out as per the "splash"