GDC Tricks of the Trade 2016 has some amazing tips from industry veterans. If you haven’t seen this already you need to watch it right now!
GDC Tricks of the Trade 2016
Jason Shum – Videos
Jason Shum is a senior animator at Riot Games and has some awesome free and paid videos on workflow planning, combat, traversal and more!
Kristjan Zadziuk – Youtube
Kristjan Zadziuk is an animation director at Ubisoft and has a bunch of great youtube videos that include game animation, motion matching, showreel reviews and more!
Transformation Breakdown
A workflow breakdown by Adam Turnbull of how he morphed between three different rigs
Animator's Resource Kit 