u/AmbassadorBinturong

Hi! I discovered this little guy on my sponge filter this afternoon. All of my plants and decor are over 5 months old and this is the first time spotting this. I thought it was an assassin snail at first, but it has these segmented layered-like spirals with little spines on them.

Is it a quilted melania? Are they bad or can I keep him around? It's pretty awesome looking.