IMPORTANT EDIT AT BOTTOM OF REPLY!
Something you should note is that this is temporary, more than a year ago Roblox announced changes to the animation engine which included fixing a bug, but it lead to a lot of confusion because of common use of that bug. Basically,
-Animation1 starts playing. It has a weight of 1
-Animation2 starts playing, it also has a weight of 1
What the old system used to do was make Animation1 stop so that Animation2 played directly over it, until Animation2 ended. This was a bug, undocumented and unintentional behaviour. What NOW happens is that Animation1 and Animation2 are blended, so Animation1 contributes 50% and Animation2 contributes 50%.
You can prevent this from happening by changing the weight of the animation or changing the priority.
Option 1:
Use AdjustWeight so that Animation1 doesn’t do anything until Animation2 finishes
Animation1:Play()
Animation1:AdjustWeight(0)
Animation2:AdjustWeight(1)
Animation2:Play()
Animation2.Stopped:Wait()
Animation2:AdjustWeight(0)
Animation1:AdjustWeight(1)
Option 2:
Set the priority of Animation2 to be higher than the priority of Animation1 in the Animation Editor.
For example, if you set Animation1s priority to “Idle”, then you can set Animation2s priority to “Action” for Animation2 to override Animation1.
(Note: I’m referring to Animation1 as the “default”, “idle” or “weapon holding” animation for your game, and Animation2 as the “attack”, “main” or “mouse click” animation for your game, the one where the pitchfork is reaching out in your case)
Edit:
VERY IMPORTANT: The AnimationWeightedBlendFix WILL be removed at some point in the near future! DO NOT rely on it! You WILL have to choose an option, else your games animations will be broken when Phase 3 rolls out!