Back during the original Equivalent Exchange 2 days, me and the destruction catalyst had all sorts of fun, usually at the expense of a few chests full of something. There's a reason my Minecraft Forums signature is "So there I was, knee deep in cobblestone for the fifth time that day". One time, I managed to take out a good chunk of my obsidian factory with it.
More recently, I had my first Thaumcraft 6 "I did a stupid and now the flux levels are sky-high". Cleared a full jar of herba, wondered why I kept taking damage any time I went near my essentia/infusion area. Half an hour later, I finally go topside (I have a tendency to build cave-rooms just under the surface). "Oh. That large blob of tainted ground that wasn't there last time probably has something to do with it".
Then there was the time in 1.10 where I was having the hardest time finding mushrooms. I eventually found them in a precarious platform in the nether, and I think to myself "ok, need to be careful getting back". 30 seconds of trying to find my path back to more solid ground, and something (I think it was a nitro creeper) surprises me and I fall into the middle of a lava sea below. The gravestone mod did not help at all that time around.
