Additive animation is a powerful feature showcased in other game development engines, but it is something that Roblox lacks. I’m here on behalf of many developers who would greatly benefit from this addition.
Additive animation differs from blended animation in the sense that two animations can directly add onto each other to combine into a new animation, rather than blended animation simply mixing the two into an interpolated one.
Support! Currently I am trying to get Roblox IK and animations to play nicely, and I think that additive animations would be perfect for this.
Edit: Now that I think about it, in my case it makes more sense for there to be an additive option for IK, not animations… but I still support this cool feature request!