Baneling

The baneling is an explosive zerg strain in StarCraft II, evolved from the zergling.

Overview
Banelings are created from zerglings following a brief chrysalis phase. In the new form, the zergling's claws shrivel and become withered, and a swollen sac filled with volatile chemicals grows out of its back.

Banelings can waddle, but after an evolution they can tuck into a tight ball and roll around the battlefield.

The creature's only form of attack is to trigger a reaction within its chemical payload that causes it to explode with devastating force and shower the immediate surroundings with searing acid.

These living bombs are highly effective against both structures and ground forces; in fact, a clutch of them is capable of wiping out a group of vehicles and infantry in the blink of an eye. The banelings' lethality is further enhanced by the zerg predilection for burrowing. An apparently safe area can soon turn into a deathtrap as these monstrosities emerge and roll into the midst of their foes, giving them virtually no time to react.

History
The strategically unimportant Terran Dominion mining planet of Sorona came under siege by the Zerg Swarm during the Interbellum. For eight months the colonists defended the strong point of Cask from daily zerg attacks, causing the local zerg to dwindle in number. Only minor breeds such as zerglings continued to be produced after some time. However, the entire town was under threat from spore cannons, which made no effort to attack. Meanwhile, the colonists contacted the Dominion daily, but received no reply.

The colonists through their biggest problem was supplies, and they had to subsist on a native acidic mold. Accidental "reinforcements" from the 128th Platoon arrived, who helped defend Cask.

Medic and former scientist-in-training Maren Ayers came to believe the zerg were deliberately reducing their numbers in order to speed up evolution. She took samples of dead zerglings and discovered they had incorporated the local mold into themselves. Accidentally detonating a mold blister, she destroyed her primitive lab room. Her unusual behavior prior to that event convinced the 128th's commander, Lieutenant Travis Orran, that she had been attempting suicide.

s had driven the development and engineered a morph that could contain the energies until just the right moment.

For a week the zerg did not attack, and scouts finally located large numbers of "sick" zerglings. They were killed, but too late; the new baneling brood swept into Cask and eventually destroyed it. Meanwhile, the spore cannons were used to transmit genetic information to the rest of the Swarm.

Ayers and Orran were the only survivors recovered by the Dominion, and both were subject to interrogation. Ayers revealed her findings, but also detonated a hidden baneling blister as revenge for the Dominion's abandonment of Sonara.

Terran Reaction
When terrans first encountered the baneling they thought it was a mutation of a previously unknown genus rather than a morph of the zergling. The baneling was duly added to the list of threats and scientists began an effort to develop chemical rounds to detonate banelings prematurely.

An audio record of Ayer's interrogation, classified as Tactical Data L45.967.22, was extracted from the wreck of the battlecruiser Emperor's Fury.

Game Unit
Banelings are relatively large units that slowly move around the battlefield and kill opponents with a low-damage suicide attack.

As of April 2009, banelings do not roll unless they have their speed upgrade.

It is strong against marines, zealots, and zerglings. It is weak against thors, stalkers, and roaches.

Attacks
Banelings are strong against melee units and "light" buildings such as bunkers and photon cannons but are weak against ranged weapons due to their low hit points. They are designed to counter zealots, zerglings and unupgraded marines.

The baneling's splash attack does not injure friendly units. It does full damage within the splash radius.

If a baneling is killed, it explodes, dealing splash damage around it.

Banelings won't accidentally target buildings when ordered to attack units instead.

Strategies
Banelings are a powerful economy-raiding force; by using overlords to transport them into an enemy base, they can quickly devastate the workers. However, a planetary fortress is well suited to destroying the banelings. Use of raiding is recommended even until late game.

Banelings should be mixed with zerglings when facing ranged opponents because they become difficult to focus fire; even one baneling escaping the fire can destroy a mass of ranged units.

Banelings have low hit points so are best used in ambushes. They can burrow, attacking like mines, but can also attack from other hidden areas, such as behind trees, to accomplish the ambush.

Banelings are very useful against marines and zealots, even into the late game, and generally dominate units such as zerglings in combat, but zerglings can come out ahead with micro. Banelings can be defeated by marines equipped with stimpacks or defended by marauders.

As they do splash damage, banelings are effective against cloaked units. For instance, a group of dark templar attacking a hatchery can be eliminated by banelings that target the hatchery itself.

A baneling/roach combo can be very powerful against terrans. The roaches will soak incoming damage, making it easier for the banelings to reach their targets.

Baneling Development
As of April 2008, banelings have been increased in size from previous builds to make it easier to focus fire on them. In addition their splash radius was increased.