This is a small client-side compatibility patch for Yessman's Epic Fight + MrCrayFish's Backpacked. Epic Fight changes how the player model is animated and Backpacked expects normal vanilla body, so backpacks don't render at all when combat mode is active. This patch makes the backpack render correctly on the Epic Fight armature during all the animations.
Epic Fight and Backpacked are REQUIRED mods, Backpacked is available on MrCrayFish's website or here on Curseforge.
