|This article contains spoilers.|
The Fireworks were an item that could be found in Alpha 2. They made their first appearance here. The Fireworks can be thrown at the Neighbor to stun him. They are found in the Bird Room upstairs. They were one of the items that were introduced in Alpha 2. There was a handful of Firework boxes, but unfortunately do not stun the neighbor when ignited, though, in the "Fireworks Gameplay" trailer, the fireworks did in fact stun the neighbor for a brief period of time when they were ignited. Them not working in the final version may have been from switching Unreal Engine versions or accidentally tampered with, causing them to not work. The fireworks can still be ignited and set off, but have no effect on the player or the neighbor.
In Nieghbor_3, you can still find 3 boxes of fireworks, but do not affect you or the neighbor here either. After this, the fireworks went unused for a period of time, but would later return.
After entering the Beta 3 Basement, there is fireworks in the giant neighbor boss battlefield. They require a candle to ignite and can be used to stun the Neighbor. Instead of being the firework boxes, they were redesigned into rockets. In Act 3, they came back in the boss battle with giant Mr. Peterson.