Tomb Crawler

The Tomb Crawler is the desert's pre-Hardmode burrower, running the same AI as the Giant Worm: it travels through solid rock and charges out at you rather than walking. Underground it begins appearing about a hundred tiles below the desert surface and gets more common the deeper you dig. It also comes to the surface during a Sandstorm, which is where most players meet their first one. Only one exists at a time under normal conditions, so it is a single problem to solve rather than a swarm to escape.

It follows the tighter spawn rules, so a town NPC settled nearby, your own safe background walls behind you, or a character that has not moved or used anything recently will each stop it appearing. A Shadow Candle in hand or placed on the ground waives all of that when you want the opposite.

Listen for the burrow noise, which rises in pitch and pace as the worm closes, and use that to decide where not to be standing. The head is the part that matters at both ends of the exchange: it carries the least armor of any segment and it does the most damage on contact, so the clean play is to hit it head on with something that pierces and then get off the line before it lands. Segments share a health pool, so anything that connects several times per swing chews through the whole worm. In Hardmode the desert hands this role to the Dune Splicer, which is the same fight scaled up in length, speed and armor.