Nydus worm

"The kraken of earth, sand, and stone. The Nydus Worm, aka the harbinger of bedtime nightmares."

- Radio Liberty

The nydus worm is a zerg transport strain.

Overview
"They always look so happy to be pooped out of there."

- A Dominion marine, in regards to zerg exiting a nydus worm

Nydus worms pose a grave threat to areas previously thought to be secure. By the Second Great War, the nydus worm was an evolution of the nydus canal. These worms live inside a nest-like structure called the nydus network and can travel from the network to any nearby location that is seen by the user before emerging, in the process creating a tunnel beneath the battlefield. This huge creature is capable of stretching itself out to prodigious lengths to support the tunnel with its own skin and ribs. Nydus worms are specialized lifeforms that have no brains of their own, only a simple array of organs that react to peristaltic motion and chemical stimuli from the network. This array allows the creature to navigate through difficult or rough terrain, and also helps regulate its biological functions. The nydus worm is merely an extension of the network.

Zerg warriors can enter the tunnel via either the worm’s head or network, and can travel through the worm at great speed due to a combination of peristaltic motion and chemical stimulants that direct their movements. To transport the Swarm’s land creatures across any battlefield or landmass, the nydus worm can stretch indefinitely through on-demand tissue generation. Ever-connected to the nydus network, the worm expands and replicates its cells at a simple command to cover the distance to its target. Surplus tissue is re-assimilated once the worm returns to the network.

The very large, thick teeth located throughout the mouth of the nydus worm primarily serve as digging tools. Each fang is connected to a set of powerful muscles, which vibrate at hypersonic speeds in order to crush soil, rocks and everything in between. Eventually (mainly due to friction) the worm’s teeth wear down. Once a tooth becomes useless, it is ejected and a new one grows from the muscle itself in a matter of seconds. When the worm emerges, gigantic spikes protract from its body when it emerges, stabilizing the creature and supporting its weight while the Swarm advances from the depths of the nydus network onto its target area.

Nydus worms generate tons of detritus, but they dispose of them in a rather efficient way. First, the crushed rock and soil is covered with a strain of corrosive creep secreted by glands located around the creature’s large maw. Once it liquefies, the detritus trickles down into twin passages that transfer it to a specialized layer under the epidermis, improving the weight distribution of the tunnels they support with their skin and ribs.

Once the first worm tunnel is excavated, more can be ordered, one at a time. All nydus worms and networks are directly connected to each other. Before long, the entire battlefield can become accessible to the zerg. However, the worms aren't particuarly durable for their size.

Nydus worms were used as early as 2502 on Urona Sigma.

StarCraft II
The nydus worm can spawn on any 3x3 patch that is clear of the fog of war. Deploying on creep is optional.

The nydus worm grants access to the "nydus system" through the UI. Nydus worms and networks act as portals into and out of the system. Units are loaded into the system, and may not be attacked while inside. Loaded units are lost only when all portals are destroyed.

Air units, mobile crawlers, and allied units cannot be loaded into the system.

The nydus worm can be used to transport as many units as are selectable. These units are visible within the system. However, the UI displays only the first couple of units per supply-level.

Unloading all units from a nydus worm makes them exit one-by-one in the order they entered the system. All units, regardless of properties, take the same time to unload. The unload command does not affect units who enter the network while unloading is in progress.

Each worm can be given a rally point. Units which exit that particular worm automatically attack-move to that point.

When a nydus worm finishes spawning, a screeching sound and a text warning are issued to all players. This alerts players. This is unlike the nuke warning, which gives time to react.

A nydus network may spawn only one nydus worm at a time, although spawning may be queued. Having multiple nydus networks allows multiple nydus worms to be spawned simultaneously.

Heart of the Swarm
Nydus worm variants called Greater Nydus Worm appear in several missions, but cannot be controlled by the player. Their description says they are a "powerful nydus worm strain capable of tunneling across incredible distances." They function identically to the normal nydus worm, save for higher HP (1000). An associated "greater nydus network" structure also exists, but other than being able to summon greater nydus worms, it is identical to the normal nydus network.

Legacy of the Void
In Legacy of the Void, nydus worms are invincible while emerging. The main effect of this change is that workers are no longer a viable defense against nydus worms.

Co-op Missions
A special infested version of the nydus worm will appear on the Dead of Night map as a boss infested.

Left 2 Die
A powerful variant of the nydus worm appears in the Left 2 Die map. They have more hitpoints, and continue to spawn infested until destroyed.

Strategies
Nydus worms can quickly transport units between multiple zerg bases, in a manner similar to nydus canals. A pool of units can be kept in the "nydus system" to emerge at a moment's notice at any of the system's entrances. This can be used to move drones to and from expansions.

Use multiple nydus worms to attack an enemy base; single worms are easily destroyed due to their low hit points. Spawning multiple worms near multiple bases may be used to feign attacks and test defenses; troops can be sent against bases which are not reinforced.

Units unload in the same order they are loaded; manipulate the load order so an attack is spearheaded by the most appropriate units.

Blizzard has noticed that nydus worms aren't being as used as often as they would like. They are considering making changes to the unit, but would like to keep it distinct from the overlord, in regards to being a riskier, but more effective zerg transport in-game.

Heroes of the Storm
Nydus worms can be summoned by Zagara in Heroes of the Storm.

Overwatch
A nydus worm slide features as an attraction in the Blizzard World map in Overwatch.

Variant Strains

 * Creep tower (cut content)
 * Meinhoff worm
 * Nydus destroyer (cut content)
 * Omega Worm
 * Underfiend (cut content, likely variant)