We had an issue with mice coming inside at our old house. But we had 7 cats, so the problem was I would come into the kitchen in the morning to find blood streaks on the floor where the cats had their fun with the latest intruder. Then I had to dispose of the body. So I never had to partake in the cruelty myself, but I had to deal with its aftermath.
The mice never seemed to figure out that ours was a house of death. But we had a really cool exterminator that wouldn't try to up-sell us on stuff. He always gave us good advice on dealing with various pests. He helped us find the places where the mice were getting in the house and seal them. That's the best solution if you can do it.
I think it could make a pretty good game, actually. You know how some games unlock difficulty modes when you beat them? Do something like that, but with different villains. You beat the game, then you can play it again with a different bad guy. They could make a few bad guys to swap into the game with each one getting a bit harder, like they've learned from the mistakes of their predecessors.