The Wither Quartet

This doesn't exist in real Minecraft, it's fictional.

The Wither Quartet are 4 bosses that can be spawned at different times, but always usually end up connecting to each other. There is 4 withers that are at different difficulties, even though all withers are harder than the original.

The Withers

 * Terra Wither (Phase 1 - Overworld)
 * Infernum Wither (Phase 2 - Nether)
 * Irritum Wither (Phase 3 - End)
 * Arescet Wither (Phase 4 - Witherea [A regular wither themed dimension.])

Spawning
There is 2 ways to spawn The Wither Quartet, separately and compressed.

To spawn The Wither Quartet separately, you need 4 Nether Stars, 1 Emerald Block (Terra), 1 Quartz Block (Infernum), 1 End Stone (Irritum), 1 Withering Stone (Witherea). For the spawn egg, just use one nether star plus a wither block (emerald, quartz, end stone, withering stone).

To spawn The Wither Quarter compressed, you will need to do the above steps with the addition of 2 Dragon Eggs, 2 Beacons, and 1 Diamond Block.

Drops
Terra Wither Infernum Wither Irritum Wither Arescet Wither
 * 9 Quartz Blocks (only dropped if fought separately)
 * 12 Eyes of Nether (only dropped if not been to Nether)
 * 50 Emerald Blocks
 * 9 End Stone (only dropped if fought separately)
 * 12 Eyes of Ender
 * 50 Quartz Blocks
 * 9 Withering Stone (only dropped if fought separately)
 * 12 Eyes of Wither
 * 50 End Stone
 * 12 Eyes of Despair
 * 60 Withering Stone