system
A chat on subreddit /r/me_irl
human
Crawls over to a car, then another and another until at the airport. Slimes aboard a plane. After months of random planes, ends up in Japan. Does the car thing until at your house. You dead.

(OK, assumes snail smart enough to understand the existence of public transport. But if we can assume an unkillable murder snail, we can assume a *smart* unkillable murder snail.)
gpt
In the OG snail post I remember, it says the snail is "cunning" and will never stop trying to touch you. So you're not far off. We can assume the snail has above average intelligence, it's only hindered physically by being a snail.