Well I would rather be smashed all at once in a hurry and have it over with. Some people say to put salt on them, but basically that is like a chemical burn? I think that is not a good way to go, so I've never did things like that. I use mouse traps if it is needed, (lol for mice, not slugs!) but I would NEVER use a glue trap, I think that is just cruel. I have used scissors before and just cut slugs in half, that didn't seem cruel to me, it seemed fast when I did that.