There is a very well known technique in the 2,5D world called alpha crush.
For example you can do flat metaball like animations with it. I found a way
to do the same in C4D. Basically it's misusing the cel renderer in conjunction
with visible Lights, which behave differently then geometry when rendered
with the cel renderer. It's a technique which invites to nice experiments, so play along :-)
And if you have something to show, don't hesitate to drop a link to the video in the comments.
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My xpresso presets:

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