so, personally, I don't have access to this. however, a basemate of mine wants to change our spawner to a creeper to better utilize explosive generators. however, creepers aren't an option. maybe we could add that in? Thanks in advance!! -Mrminesheeps
correction, while it is not likely, creepers CAN show up in dungeons. it has been seen before. looked it up, apparantly they aren't on the list now but I distinctly remember them being on the list at one point or another, it was just a low chance, ~10% of dungeons had one.
I see your logic, but we currently cannot turn spawners into Blaze, which are vanilla-spawners. So, if we're revisiting options like this, I would suggest adding Blaze as well.
The problem with that logic is that I am pretty sure that I haven't seen cow spawners in a normal world either ;-)
Vanilla never had creeper spawners, maybe because people would be able to just let a creeper blow up and get rid of the danger. Might have been in a modpack tho.