[skeezyboy]

if you look on the top of its head its got two arm like appendages that it can touch things with, probably did it with those

[inkcapmushroom]

Those are its eye stalks. I don't imagine pressing with a lot of force on its eyestalks is something a slug likes to do, but then again I haven't asked any yet.

[skeezyboy]

it was ringing the bell somehow, what else could it have been? even a particularly fat slug would have trouble pressing the bell as its vertically aligned.