Burrowers

Burrowers (commonly known as "background ore worms") are a multi-segment enemy that can go through blocks. While being dangerous to the player, they are also very lucrative to fight, because they cause a lot of ore to become embedded into the background blocks. This only happens if they are defeated in front of the background wall.

They are very vulnerable to weapons that can hit multiple parts of their body, including flamethrowers and Mining Laser.

Aside from regular worm monsters, there is a very strong mini-boss called Doomwyrm, which is also a Burrower.

Location
Burrowers appear in many underground biomes, and almost any planet can have then. They don't appear on the starting Garden planet.

Type of the burrowers depends on many factors (depth, tier, planet type, etc.).

Behavior
Burrowers are unique monsters, found generally in the underground caves of any planet high in ore and gem deposits. It is unclear what first created these creatures, however each variety has striking similarities. Every variety of Burrower is composed of long body segments that have utilized the materials the creature devours so fully that the body segments themselves seem to have integrated the preferred minerals and ores. Each Burrower is lead by a "head" segment, in which each "body" segment is attached. Destruction of the head, or severe enough damage to the several body segments will eventually lead to the death of the creature. At this point, there is a total of 40 known Burrowers, each composed of one unique material or ore, in which the creature most commonly eats.

The introduction of a Burrower into an area can cause catastrophic damage and in many cases collapses of entire ecosystems. Digging vast networks in search of their favorite ore, Burrowers destroy and tunnel with reckless abandon in search of their preferred meals, only stopping long enough to attack any living organism encountered, or devour entire veins of ore. It is clear that Burrowers are not native, nor natural to the any of the environments they have been reportedly found in. As such, it is believed that these creatures were developed as a means of aggressive mining - for once released, they will accumulate ore within themselves, making these creatures quite valuable to those in search of the precious materials that the creatures themselves devour, and in turn are composed of.

All varieties of Burrowers primarily attack in a rather straightforward pattern of charging the nearest living organism and slamming their dangerously jagged and steely bodies into them. Within each type of Burrower however, lies vastly different capabilities.

Types
There are currently 40 known varieties of Burrowers. Each type shares the similarity of being composed of three distinct parts - a single head entity that serves as the creatures mouth and guide - each other segment type will follow this entity. The second part is the body segments, which can be comprised of several different looking body types. It is typical for there to be a range of 5 - 15 body segments comprising the creatures body. The last distinct part is the creatures tail, which can be composed of high damaging, unique looking segments ranging from 1 - 5 parts in length.

See below for examples of each variety.
 * Aegisalt Burrower: A camouflaged worm burrowing through the earth composed of aegisalt
 * Copper Burrower: A camouflaged worm burrowing through the earth composed of copper
 * Core Fragment Burrower: A camouflaged worm burrowing through the earth composed of core fragments
 * Densinium Burrower: A camouflaged worm burrowing through the earth composed of densinium
 * Diamond Burrower: A camouflaged worm burrowing through the earth composed of diamond
 * Direstone Burrower: A camouflaged worm burrowing through the earth composed of direstone
 * Dirt Burrower: A camouflaged worm burrowing through the earth composed of dirt
 * Doomwyrm (Mega Burrower): A massive, deadly worm. Definitely not natural. Exclusive to Aether and Sulphuric Worlds.
 * Durasteel Burrower: A camouflaged worm burrowing through the earth composed of durasteel
 * Ferozium Burrower: A camouflaged worm burrowing through the earth composed of ferozium
 * Gold Burrower: A camouflaged worm burrowing through the earth composed of gold ore
 * Iron Burrower: A camouflaged worm burrowing through the earth composed of iron ore
 * Irradium Burrower: A camouflaged worm burrowing through the earth composed of irradium ore
 * Isogen Burrower: A camouflaged worm burrowing through the earth composed of isogen ore
 * Koanite Burrower: A camouflaged worm burrowing through the earth composed of koanite
 * Lead Burrower: A camouflaged worm burrowing through the earth composed of lead ore
 * Lunari Burrower: A camouflaged worm burrowing through the earth composed of lunari shards
 * Magnesium Burrower: A camouflaged worm burrowing through the earth composed of magnesium
 * Mascagnite Burrower: A camouflaged worm burrowing through the earth composed of mascagnite
 * Moonstone Burrower: A camouflaged worm burrowing through the earth composed of moonstone
 * Neptunium Burrower: A camouflaged worm burrowing through the earth composed of neptunium
 * Penumbrite Burrower: A camouflaged worm burrowing through the earth composed of penumbrite
 * Platinum Burrower: A camouflaged worm burrowing through the earth composed of platinum ore
 * Plutonium Burrower: A camouflaged worm burrowing through the earth composed of plutoniuma
 * Prisilite Burrower: A camouflaged worm burrowing through the earth composed of prisilite
 * Protocite Burrower: A camouflaged worm burrowing through the earth composed of protocite
 * Pyreite Burrower: A camouflaged worm burrowing through the earth composed of pyreite
 * Quietus Burrower: A camouflaged worm burrowing through the earth composed of quietus
 * Silver Burrower: A camouflaged worm burrowing through the earth composed of silver ore
 * Solarium Burrower: A camouflaged worm burrowing through the earth composed of solarium ore
 * Stone Burrower: A camouflaged worm burrowing through the earth composed of stone
 * Sulfur Burrower: A camouflaged worm burrowing through the earth composed of sulfur
 * Thorium Burrower: A camouflaged worm burrowing through the earth composed of Thorium
 * Titanium Burrower: A camouflaged worm burrowing through the earth composed of Titanium
 * Trianglium Burrower: A camouflaged worm burrowing through the earth composed of trianglium
 * Tungsten Burrower: A camouflaged worm burrowing through the earth composed of tungsten
 * Uranium Burrower: A camouflaged worm burrowing through the earth composed of uranium
 * Violium Burrower: A camouflaged worm burrowing through the earth composed of violium
 * Xithricite Burrower: A camouflaged worm burrowing through the earth composed of xithricite ore
 * Zerchesium Burrower: A camouflaged worm burrowing through the earth composed of zerchesium ore

Luna's Lab Notes
~ Each type of Burrower is quite complex made up of three separate monster types - A "head", several "body" segments (usually 5-15), and a "tail" which can also be composed of multiple segments. Additionally, there are several unique body segments that are chosen at random when generating a burrower, leading to varied, and good looking wyrms. Additionally, the health pool is linked for these creatures, so dealing damage to the body can technically kill the whole creature - however it seems the head is significantly more susceptible to critical hits.

~ In the files this creature is coded to be capture, however there is not a proper input for the creatures name upon capture. Additionally, the "head" and "body" spheres existing as different monsters, yet also being linked in the coding, leads to neither the "head" or "body" being tangibly captureable until the moment one type dies, at which point they are all considered dead.... Which results in the monster being uncapturable even with use of admin commands.

Source:  https://github.com/sayterdarkwynd/FrackinUniverse/tree/master/monsters/segmented/burrowers