Place the Oreos in a large ziplock bag and crush them using a rolling pin until you have a mix of fine crumbs and small chunks. Add melted butter and mix well, then set aside.
In a bowl, whisk together the milk and pudding mix until it begins to thicken, then set aside.
In another bowl, beat the softened cream cheese and powdered sugar until smooth and lump-free.
Add the prepared pudding to the cream cheese mixture and mix until fully combined. Gently fold in the whipped topping until light and creamy.
In your serving dish, spread a layer of pudding mixture at the bottom, followed by a layer of the Oreo mixture. Continue layering until everything is used, finishing with a layer of Oreos on top.
Decorate with gummy worms if desired, then refrigerate for at least four hours or overnight before serving.