|Health points||400 ( × 200)|
The Mourner is a boss added by Defiled Lands. It can be summoned by using an Idol of Sorrow on an active Conjuring Altar. When killed, it drops 4-16 Defilement Powder, 8-16 Umbrium Ingots, 4-8 Scarlites and 8 Remorseful Essence.
The Mourner floats above ground and can pass through walls, similarly to a Vex. When targeting a player, it will move to random locations around its target, teleporting if it gets too far away, and periodically uses one of its 3 attacks. Each attack has a warning animation, allowing players to know which is going to be used, which are as follow:
- Right arm pointed at target + fire particles: fire a volley of Blaze fireballs towards its target
- Left arm pointed at target + End Rod particles: fire multiple Shulker projectiles homing on its target
- Both arms raised above its head + smoke particles: fire multiple Ghast fireballs at its target
On top of that, if a player gets too close to The Mourner, it will cancel its current attack and charge at the offending player, dealing 16 () damage on hit and knocking it away a large distance. It will then resume its standard behavior provided the player was knocked away far enough.
After falling below 50% health, a red eye appears on The Mourner's face (similarly to a Twisted Shambler), faint red marks appear on its clothes and it will start shaking. This causes it to move faster, attack more often, fire more projectiles per attack and increases the explosion strength of its Ghast fireballs.
After falling below 25% health, the red marks on its clothes become much more pronounced and it will shake more violently. This increases the bonuses from the previous stage even more.