The Wraith is a Hard Mode monster that was introduced in the 1.1 update. This mob is not solid and can therefore pass through blocks.
Wraiths will also be summoned upon the destruction of a Demon Altar or a Crimson Altar.For every Demon or Crimson altar destroyed, 1-3 wraiths will spawn. The Wraith, like other creatures able to pass through blocks, can be damaged through walls with any melee weapon, as well as by spells such as the Vilethorn while they are still inside a wall.
When Wraiths are not passing through blocks, they are unable to hover higher than 3 blocks in height. Keeping NPCs above that height will ensure that Wraiths don't kill them. A house should be built 6 blocks off the ground to completely Wraith-proof it.
Wraiths are dark, which sometimes makes them hard to spot at night or when they pass through blocks. However, their eyes can give away their position because of the distinct red color.
Once a Wraith is killed, it will explode into a puff of black smoke and vanish.
The Reaper can be considered a more powerful version of this enemy.

Update Info[]
- Health decreased from 200 to 160.
- Added to the game.