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Blender - Blender is the open source, cross platform suite of tools for 3D creation.
Spine - Spine is 2D animation software designed specifically for software and game development.
Cinema 4D - Cinema 4D is a 3D modeling, animation, motion graphics and rendering application.
Animation Paper - Animation Paper is a software package for doing 2D animation.
Autodesk Maya - Maya is 3D computer animation software with powerful modeling, rendering, simulation, texturing, and animation tools for artists, modelers, and animators.