Memes

There's a couple of mods that do that, but I remember watching a streamer nuke a small town for the luls (his fans were on server and were cool with it). Nowadays most packs have anti-greving stuff, though, which is a double edged sword as claimed chunks can't even get damaged by creepers.

That said, I think my favorite is Thaumcrafts oopsies--- too much magic, you get eldrich horrors tearing the very fabric of reality. It's very unsettling and does turn every block to a corrupted stone that's a pain to break.