The Hallow

The Hallow is a new biome that is created once you have defeated the Wall of Flesh in the Underworld. It is an anti-Corruption biome and can be spread by planting Hallowed Seeds or throwing Holy Water and is most effective when used to counter the spreading of Corruption.

The biome has light blue grass and colored trees, and the background has a big rainbow. It is home to Unicorns, Pixies, and Gastropods.

The Hallow has its own underground level, the Underground Hallow, primarily made of Pearlstone, a white colored Ebonstone-like block converted from normal stone. Much like Ebonstone, Pearlstone takes longer to dig than normal stone. To dig Pearlstone, you need at least a Nightmare Pickaxe, which is made from Demonite.

The Dryad can say what the percentage of Hallow and Corruption is in the world, once the Wall of Flesh has been defeated.

The Hallow can spread both on the surface and Underground.

Purification Powder has no effect on the hallowed ground; However, Vile Powder can return hallowed ground to the default biome of the world

Spreading
The Hallow can be spread above ground with Pearlstone Blocks, Pearlsand, Holy Water, or with Hallowed Seeds.

The rules for hallow spreading are as follows:
 * Pearlstone and Pearlsand blocks will spread The Hallow to adjacent stone, sand, and grass blocks (pearlstone will not spread The Hallow to dirt blocks without grass growing on them).
 * When planted, hallowed seeds will spread The Hallow to adjacent dirt, stone, sand, and grass blocks.
 * The Hallow cannot spread to mud blocks; therefore, the Hallow cannot spread through jungle.
 * Sunflowers will not impede the spreading of The Barrier_demo.jpgw.
 * Hallow will not spread through gaps in the environment that are three or more blocks across.
 * Hallow will not spread through synthetic blocks (ie. materials such as Gray Brick) that are three or more blocks across.
 * Vines growing from hallowed ground can spread The Hallow through proximity.
 * The Hallow can be planted in world, where no Wall of Flesh has been killed, although it won't spawn any Hallow monsters and doesn't spread through sand, stone and normal grass.