The Ancient Herald is a boss monster that spawns during the Aporkalypse. If killed, it will respawn indefinitely, until the Aporkalypse ends.
The Ancient Herald will rise from the ground somewhere on the player's screen a short time after the Aporkalypse begins. It will slowly pursue the player, losing interest if the player gets far enough away and then despawning after a while. If the player returns to the Ancient Herald, it will not be aggressive unless attacked.
It attacks by diving into the ground, emitting a shockwave that destroys structures and damages nearby enemies, setting them on fire similar to the Iron Hulk Head or Leg. In addition, it will periodically cast an incantation, summoning various creatures and attacks to help it. Each new Ancient Herald that spawns seems to 'prefer' certain summons than others, casting them far more often than it does any other.
- 4 to 5 Ancient Spirits.
- 2 to 4 Nightmare Creatures.
- 1 to 3 Dragoon Eggs, that leave Lava Pools.
- ~9 to ~20 Poison Dartfrogs in a circle, slightly offscreen.
The various monsters it spawns, coupled with the destructive power of its attack, means that this boss is very difficult to fight. Since it drops nothing, and respawns quickly, there is currently no benefit to killing it. The wisest choice is to simply run away.
The Ancient Herald resembles a skinny, nightmare version of a citizen of the Ancient Civilization, having the same tail, stubs where its legs should be, bug-like claws, spikes protruding from it, and a hunched posture. The marking at the top of its head bears a striking similarity to the pincer-like symbol in the middle of the Ancient Gateway as depicted by the artwork on the Ancient Civilization page.
It is possible, according to inspect quotes of Ancient Mural #3, that this is what the insectoid creatures turned into due to the Nightmare Fuel.