Nether
1. The Nether is also known as "the Nexus" in Notch's blog, and previously, Hell or the Slip.
2. Locations in The Nether correlate to Overworld coordinates, but Nether distances are scaled down by a ratio of 8:1.

Mobs
3. The probability for a Wither Skeleton to drop a Wither skeleton skull when killed is 0.025 or 2.5%.
4. Ghasts make screeching and whimpering noises, something like a purring kitten or an angry baby (actually taken from C418's cat disc).

Environment
5. Lava flows more further in the Nether than in the Overworld.
6. When ice melts in the Nether, it will not melt into water (versions 1.5 or earlier).

Pocket Edition
7. For the moment, there is no kind of Nether in the Pocket Edition.
8. There is a structure known as the Nether Reactor. It is built from 14 blocks of cobblestone, 4 blocks of gold and 1 Nether Reactor Core.

Other Facts
9. The idea for the Nether came from a transportation method used in the novel series The Wheel of Time by Robert Jordan.
10. If the player stands on soul sand with lava at the same level adjacent to the soul sand, the player will take damage if he/she steps near the edges of the soul sand. This is due to soul sand being slightly smaller than other blocks.

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