Invasion

At all times, there is a small chance that the surface will be invaded by a horde of monsters.

Until all invading monsters are defeated, all shopkeepers will disappear.

The following monsters will appear above the corruption:
 * several
 * several
 * several that will spawn . These will begin showing up at higher levels.
 * several that will start showing up at level 75.
 * Mele or Ranged . With the ranged commander showing up at higher levels.

Tips
 * All invading monster locations are visible on the map, marked by a red circle.
 * The can be used to access the bank storage during invasions.
 * The Corruption of It surface and NPC buildings are unbreakable, so they're a good spot to kill Invasion Ogres.
 * The Invasion Commander drops weapons equal to your character's level.