I was responsible for preparing all characters for animating. We used Maya built-in HumanIK for human body rigs, while for faces I've developed the custom unified FACS rigs, which involved Set Driven Keys (SDKs) and joints-only deformations with max 4 influence per vertex limitation (for usage in proprietary 3D-engine optimized for iOS). It was completely character-agnostic, i.e. the animals, creatures and human characters could be driven exactly the same way. This ensured that the animator could make one facial animation and then copy it to all other characters in a fraction of time. And by the way, this rig allowed us to achieve the unprecedented quality of facial animation across all mobile products on the market.