NOTE: Newer versions of Unity have introduced updates which make it very easy to scale particle systems together, and many of the features of this asset are becoming increasingly obsolete.
I'd recommend first testing out the native scaling features for particle systems in Unity before purchasing this package to determine whether you really need the extra capabilities (which depends on which version of Unity you're using).
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Easily scale Shuriken ParticleSystem components either individually and directly, or in sets and embedded hierarchies.
Open up the editor window from the menu bar:
>> Window -> Mirza Beig -> Particle Scaler.
Simply select any ACTIVE GameObject(s) in the scene that have at least one ACTIVE ParticleSystem component in their hierarchy. The component(s) can either be directly on the selected object and/or parented child objects.
You can preview your selection(s) without actually having to play your scene (play, pause, stop from within the extension itself), and apply the results as you scrub through the slider.
Undo and redo are supported.