The Obsidian Cube is a 5x5 cube made by Runt. It was created during Project Squidboat, a collaboration between Runt and Emerald set up by Drill.
Popularity of Cube
The humans and villagers enjoyed watching the mobs attacking the cube. According to Runt, practically the whole town was above, on the wall, watching. When it started raining, the mobs stopped attacking it and the mayor told everyone to inside to their homes.
Ways the Mobs Attacked It
1. They tried to explode the cube with creepers. A zombie counted to three to make sure all the creepers exploded at the exact same time. Despite that, the cube did not lose a single block.
2. In addition to regular creepers, they used charged creepers, (a creeper who gets struck by lightning and becomes more powerful than a normal creeper.)
3. The mobs used enchanted iron pickaxes to try to mine the obsidian cube, but it didn’t work since diamond pickaxes are the only common tool that can mine it.
4. The mobs tried digging under the cube to see if there is an obsidian floor. They discovered there was indeed an obsidian floor.
Aftermath of Cube
The mobs presumably got annoyed by looking at the cube and buried it under dirt. Runt says he is planning on uncovering it to mess with the mobs. However, Runt never again mentioned it. Whether the Cube is still there is unknown.