I don't get how the armory works, is it supposed to be a practice area for stuff and you can't use the weapons outside of their levels? because it sounds like you can use them in other levels but I don't know how I would do that if that's the case. (or am I just stupid?)
Viewing post in Candies 'n Curses in Baba is You comments
The Armory is called "Training Room" in-game and it's there to test weapons you unlock from the Dog's Arsenal Training side story with infinite energy. Unfortunately, you can't pick your own weapons as it is predetermined from the start of the level because of BiY limitations.
The Training Room was a byproduct of me brainstorming with weapon ideas during development, but I thought it'd be neat to make it playable.