Reaper

A Reaper is an enemy that spawns during a Solar Eclipse event in Hardmode.

They are functionally similar to Wraiths, but with higher numbers in their stats. They are far more dangerous than normal Wraiths, as they not only do enough damage to be threats to even late-game-armored players, but also move significantly faster than wraiths, and, thanks to the higher spawn rate of the Solar Eclipse, often attack from multiple directions at once.

Fortunately, they are quite vulnerable to knockback, and like many creatures that pass through blocks, weapons that normally don't harm enemies through blocks, like most melee weapons, will damage them.

Similar to Wraiths, they are incapable of ascending more than a few tiles above solid blocks. Standing on a platform several tiles above the ground or use of wings or rocket boots allows players to shoot down upon them with impunity if they are going to be surrounded.

They are immune to all debuffs and lava.

Trivia
Reapers have glowing violet eyes, as opposed to Wraiths' red eyes. In addition they also have violet glowing hearts. This may be because in some cultures deep purple is often associated with death.