Even thou zBrush can be used as a stand alone app

It's used as a plug for a lot of other app's DAZ,Poser,C4D,
Max .AutoDesk has MudBox.Games

I don't know Blender that well but it has a lot of tools including sculpting and it's free.

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The Artist that will fight for decades to conquer their media.
Even if you never know their name ,your know their Art.
Dark Sphere Mage Vengeance