FPSC isn't free to actually build games, you will only be able to play them in editor. x10 is more expensive but despite some nice shaders, the lack of support and new development direction doesnt make it worth the money to me. If you want a better FPSC experience, just shell out the tiny bit of dough it costs to buy it and update to v1.18 or v1.19 which is a much more stable complete build and able to create decent games. To see the upper extent of what you'd be able to create in FPSC: (assuming you learned the FPI scripting language and learned how to model, uvmap, rig, and texture in a 3d modelling program)
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making games is no easy task. beware what you're getting into and the hopeless addiction it may form
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