Simplest FREE 3D Game Making Software?

I would like to know the best free 3D game making software for the PC. I would like it simple, free, and can be internet based (multiplayer). I want PROFESSIONAL answers, thank you.
I would like to know the best free 3D game making software for the PC. I would like it simple, free, and can be internet based (multiplayer). I want PROFESSIONAL answers, thank you. Quake 3 Would be nice, but I don’t know were to start.
Not 2D please. GameMaker is 2D as far as I know.

Weeeellllll
blender
but you know, it’s hard and you need 3d models, but you can model and create games in it

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