Unity 2D Particle System Inward Moving Particles
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To create inward-moving particles using the stock Particle System in Unity, you need to set the Start Speed to a negative number. This reverses the direction of the particles so they move towards the center.
In addition to the Start Speed, you'll also need to set Emit from to Volume Shell and then adjust Radius and Length under Shape. Fiddle with it until you get the effect you're after.
Here are example settings:

In addition to the Start Speed, you'll also need to set Emit from to Volume Shell and then adjust Radius and Length under Shape. Fiddle with it until you get the effect you're after.
Here are example settings:
