Cosmivengeon/Desolation Mode

 is a new game mode added by Cosmivengeon. It can be toggled by which can be crafted at a Demon Altar or Crimson Altar, It introduces new, Tougher enemies, AI changes to Vanilla Bosses and  to make Terraria more difficult.

It also introduces a new mechanic :

=Vanilla Changes=

Desolation Mode currently only changes the following vanilla bosses:
 * King Slime
 * Eye of Cthulhu
 * Eater of Worlds
 * Brain of Cthulhu
 * Queen Bee
 * Skeletron
 * Wall of Flesh