So, I'm using Sharb's Godot Baldi port, and I wanna make it so that when you're about to get the last exit (in a specific mode) Null will spawn in the last exit and block it. And next to null will spawn a projectile which you can throw to damage him. And when you throw the first projectile at him, he starts saying his speech before following the player. And some other projectiles spawn. (I also forgot to mention the UI disappears when the bossfight is triggered)
If you want to know what it looks like, it looks like this:
Gameplay Of The Baldi's Basics Classic Remastered Null Battle