For about 8 bucks at the local hardware or big box store you can make a simple firearm. The idea behind the liberator was a single shot to get rid of an enemy soldier and take his weapon and ammo.
A simple search will show video of assembly and a parts list with how to use with examples of shooting.
As a second part, just adding pool shock and brake fluid will get you a flaming green fire.
Aluminum powder and magnesium powder in a steel tube will burn through armor when ignited with a sparkler as improvised thermite.
I could keep going, but anyone with a bit of knowledge can make improvised weapons that will work very well.
I was curious so I did a search on “improvised thermite”.
Now there’s an FBI van out front.
If I don’t post for a few days I’m probably in the bunker.
Shove a shotgun shell into a badminton birdie and a push a roofing nail into to the sponge rubber tip. Toss.