The instant I saw this Russian knock-off of the Space Gun of my youth, I had to buy it.
Disc Gun, Space Gun, Tracer gun: whatever you called it, this toy is a ton of fun! It leaves discs in all sorts of places intended to be ingested by a pet or a vacuum cleaner. As a kid, they'd invariably be chewed up and coming out the backside of one or forcing your parents to tear into the guts of the other.
Accurate enough, fast enough, and painless unless you nailed someone with an eye or eye-adjacent shot, I now keep this gun lightly loaded and on my coffee table. If a friend grabs it and goes bonkers, neither my vacuum nor dogs will be offered many opportunities.
My imagination may be messing with me, but I remember extra packs of discs for sale alongside such things as caps and paper rolls of caps.
When I was young, I had a disc gun. Now, I am young again.