Air is not exactly a block, but it is a representation of the absence of a block. There is no way of obtaining it, destroying it, or creating it. Air fills the void when a block is destroyed by a pickaxe. It is completely transparent, therefore not considered a block, as it cannot be seen, placed, destroyed, set on fire, etc. It can only be "removed" when a block is placed down. Both normal and flat worlds contain Air.
- The color of the sky/air can be changed in the upcoming 2.0 update.
- Air fills the void of every part of the game that does not have a block.