Creepers - a Closer Look
The nature of creepers is a topic that's been discussed for years. Why do they explode? What is their endless fascination with our houses? While many theories have been put forward, the Game Theorists have come up with a surprisingly sensible theory about the inner workings of everyone's favorite green monster. Enjoy!
On the other hand, it's certainly true that a plant could easily produce the makings of gunpowder or its functional equivalent -- they accumulate organic material naturally, and many sorts can fix nitrogen, which could be used to produce explosive compounds.
Earthly plants don't do that, basically because, why? Fiery explosions are excessively destructive, and there are better (and cheaper) ways to scatter seeds: organic "springs" are common seed-flingers, but if more distance is needed, it's usual to throw out a sail and ride the wind, like dandelion seeds. But of course, Minecraft is another world, and the tradeoffs may well be different.
What if the variant of peat shown here is actually a fungal infection that can seize control of, disform, and mostly encompass a deceased corpse?
It would explain the moving behaviour to a tee; humans tend to socialize, so it gives a base incentive for the would-be Creeper. If you also look carefully at the creeper, notice how there's black on its feet, rather than brown, or a moderately dark green? Those could very well be parts of some shoes that the peat didn't want to cover.
With peat's explosive nature, the evidence that MatPat presented, and the links I've created, I think we've finally arrived on a proper conclusion of what a creeper is made of, and how they function (as well as why they'd "de-spawn" on occasion).
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