Grease Pencil Rigs are a free set of basic rigs for Blender 2.8 that are for use with Grease Pencil. They are aimed to ease the drawing of characters by showing construction lines which you can use for reference while drawing.
Grease Pencil Rigs
Grease Pencil
Grease Pencil is a feature inside Blender that allows you to animate in 2D while taking advantage of a full 3D suite of features. Definitely one of the best pieces of software that blends the two together so seamlessly (and free!)
Judy Hopps Rig (Blender)
The Judy Hopps Rig is a free rig for Blender based on the character from ‘Zootopia’
Animator's Resource Kit 