I'm... Pretty sure it's just a cube that's missing it's textures.
johnmedina999 wrote:It's basically dark matter in Minecraft. It both exists and doesn't at the same time. It's both the most known and the least known substance; even the top Minecraft scientists can't determine its break time.
abraker wrote:What's is that?!?
In a word, it's impossible.
You can find slot of stuffs like that in custom maps in valve games.
If an object doesn't have it textures in the game files then it will just default to that purple texture.