Ghorm the Devourer

Ghorm the Devourer is a roaming boss found traveling in a large circle through the Clay Caves and Forgotten Ruins, at a distance of roughly 190–210 tiles from The Core. It is one of the most destructive enemies in the game, carving a path through terrain as it moves and leaving behind a long trail of Ground Slime. After being defeated, Ghorm can be summoned again by placing a Ghorm Summoning Idol on its rune, which sits below its original spawn point on the main path.

Ghorm destroys nearly everything in its path, including normally indestructible Obsidian Blocks. Most creatures are killed instantly on contact, and the boss deals 10000 damage on collision. It also fills pits and liquids with Dirt Block ground as it passes. Walls and objects broken by Ghorm do not drop as items, and ore boulders destroyed by it do not yield ore. Because of this, fighting it near anything important is risky, especially once it enters its more dangerous phase.

Ghorm does not actively engage the player until it falls to 80% health. At that point it enters a second phase and begins circling around the player, trying to deal damage directly. If lured too far from the point where combat began, it returns to its main route and starts regenerating health at 2% of its maximum every 5 seconds. Keeping the fight controlled is therefore important, since losing its aggression can undo progress.

A few practical points make the fight much more manageable:

• Bronze armor and Ranger armor are solid choices. Ranger armor is especially useful because its projectiles can pierce through multiple segments.
• Bombs are cheap to craft and do heavy damage, and they detonate immediately when Ghorm runs over them.
• Spike Traps are one of the safest ways to defeat it; around 50–150 can kill Ghorm quickly if placed where it will run over them. Wooden Spike Traps work too, but many more are needed.
• A hoe, ideally Tin or Iron, removes Ground Slime quickly and helps restore mobility after the boss passes.
• The Larva Ring and Grub Egg Necklace can negate the slowing effect of Ground Slime, and a full set of Rain armor is a workable alternative.
• Do not start the fight near structures you want to preserve, since Ghorm becomes especially destructive during its second phase.

Because Ghorm repeatedly follows a fixed route, it is often best fought by preparing the terrain in advance, then letting it run into traps or bombs rather than trying to chase it through its path.