You can Use Snowgrave on Normal enemies without hacks in Deltarune Chapter 2...

So a bit of an explanation, I've been experimenting with Deltarune's Snowgrave route and I finally figured out a way to use Snowgrave without hacking! So the requirements are do a Snowgrave route as normal but when you fight Berdly don't kill him, simply cause Noelle too say "Watch what happens when I use a spell I don't know!" but immediately after that just defeat Berdly without Snowgrave. After this backtrack until you find the cheese room and purposely touch the cheese, triggering an encounter with a Maus, you should be able to use Snowgrave on the Maus if you did everything correctly. It's a very short clip because I don't have a capture card and had to use the Nintendo Switchs shitty record feature, and I tried MULTIPLE TIMES to get a good clip of the animation and this was the best I could get