"Killing?" Even when mocking an opponent, at least be accurate; the demons possessed the pigs who then rushed into water and drowned themselves: https://biblehub.com/mark/5-13.htm

Then the villagers pleaded with Jesus to leave due to having wrecked their economy. Whether Jesus did it because He's Jewish/anti-pork or that just happened to be what the demons weirdly chose to do (or if it, uh, happened at all, of course), we may never know... But that is how the account goes, regardless.

It's less violent, but Jesus killing a fig tree because it wasn't fig season is also really funny.