The Nether is one of the three dimensions in Minecraft, The other two being The Overworld and The End. The Nether is home to a vast array of strange creatures including Ghasts, Zombie Pigmen and Magma cubes.
The Nether resembles hell, there are endless pools of lava, fire burning everywhere and it appears to be underground. However the only way of entering and leaving the nether is through a Nether Portal, there is no way of digging out. The Nether appears to be Infinite in size. The only buildings in the Nether are Nether Fortresses which are home to Blazes and Wither Skeletons.
Ghasts are bizarre giant floating jellyfish looking creatures that inhabit The Nether. They float around making whining noises and have the ability to shoot fireballs. They are one of the most difficult creatures to kill in The Nether.
Zombie Pigmen are one of the most common creatures found in The Nether. They are different to regular zombies in many ways. Firstly they only become hostile if attacked first and also unlike regular zombies, if one is attacked then all the other Zombie Pigmen nearby will attack suggesting some form of intelligence. Zombie pigmen also carry golden swords.
Magma cubes resemble Slimes from the Overworld except they are made of magma and rock. If a large magma cube is killed it will split into two medium magma cubes and if the medium magma cube is killed, it will split into 4 small magma cubes.
Blazes are fiery infernos that live in Nether fortresses within The Nether. They are extremely dangerous as they hurl bolts of fire at anything that comes near them.
Wither skeletons are large black skeletons that live in Nether fortresses.