Adding onto this, Black Magic II uses Roblox’s animation system, Animtracks and all that, combined with scripted effects. It also uses a region3 hitbox system as far as I know, though there are definitely alternatives. (such as this cool raycast hitbox system) You can remove the fade time for animations to make them feel more snappy, if you don’t feel like coding too much.
However, I would try to create your own blending function. For example,
PlayAnim(nextattack) would get the current C1 (I think Roblox animations transform C1? I might be wrong they might transform C0 instead.) of all the character’s Motor6Ds, then convert the animation you want to play into a keyframe sequence –This’ll probably work-- and then use TweenService to transform to the first keyframe of that. Since the function I linked earlier yields, it might be wise to do this once during loading and use that instead. I’ve been wanting to do this myself (and then post it on the devforum) but I am lazy.