StarCraft II: Wings of Liberty/Zerg units

Drone
In StarCraft II, Drones are no longer required to build defensive structures, the role having been taken over by the Queen.

Baneling
The Baneling is a wheel-shaped explosive Zerg strain descended from the Zergling. Banelings roll around the battlefield and kill opponents with a low-damage suicide attack caused by their explosive body chemistry.

Banelings are strong against melee units but are weak against ranged weapons due to their low hit points. A Nest is required to spawn them, which also provides upgrades.

Its splash damage does not hurt friendly units.

Brood Lord
Brood Lords take the role of the old Guardians and Swarm Guardians, but with powerful buffs. They have 350 HP and 9 range, with each explosive glob dealing 25 damage. Each attack will also spawn a Broodling.

Corruptor
During development, the Corruptor had the ability to turn enemy air units to Zerg control for a duration; it has since lost this ability, and now functions as a normal air-to-air combat unit. The Corrupter is treated as an armored unit, unlocked by the Spire; it can also mutate into a Brood Lord.

Hydralisk


Their appearance have changed slightly in StarCraft II. The most notable difference is their scythes, which now boast more spikes than in StarCraft. Their face is also slightly different from what it was before.

The Hydralisk is protected by light armor.

Infested Terran
The Infested Terran is a different unit than StarCraft's unit of the same name; they're essentially regular Marines with Zerg appendages, so instead of detonating themselves, they shoot while moving a bit slower than the regular Marine.

The Infested Marine is summoned directly by the Infestor, a Zerg ground unit.

Infestor


The Infestor is a spellcaster unit, similar to StarCraft's Defiler. It possesses abilities such as Spawn Infested Terran and Neural Parasite (a version of Mind Control). It cannot attack, but is capable of moving while burrowed.

Larva
The Larva reappears in StarCraft II. It is protected by light armor.

It can produce a large variety of units: Drone, Overlord, Zergling, Roach, Hydralisk, Nydus Worm, Infestor, Mutalisk, Corrupter, and Ultralisk.

Mutalisk
The Mutalisk made an appearance in the WWI gameplay demonstration and have been confirmed as playable units. Its attack can still strike multiple targets, bouncing to strike up to two additional targets as it did in the original StarCraft games.

It is protected by light armor.

Nydus Worm
Can be used to transport small units such as Zerglings underground.

The Nydus Worm is a StarCraft II Zerg transport unit used to transport large numbers of small units, such as up to fifteen Zerglings.

It can transform itself into a Nydus Canal, at which point units can enter it and "accessed" from any Nydus Warren or other canal. After being loaded with units, it can also transform back into a Nydus Worm for transport.

The Nydus Worm works like a Ghost nuke; the player places a beacon, and a few seconds later the Nydus Worm pops up.

The Nydus Worm is treated as an armored unit.

Overlord
The Overlord has made an appearance in StarCraft II. It functions in a manner similar to its StarCraft I predecessor (a flying Control-producing unit).

Overseer
The Overseer is a Zerg unit evolved from the Overlord.

The mutation gives it the ability to detect cloaked and burrowed units, along with an increased sight range. However, it loses the Overlord's Creep and Slime abilities.

The Overseer's sight radius expands when it stays still and shrinks when it moves.

Queen
The Queen appears in StarCraft II, though is a vastly different unit from its predecessor, first notably now walking on the ground. It functions as a Brood Mother, with abilities such as restoring health to Zerg structures and injecting additional Larva into Hatcheries. You can train a Queen from a Hive, without using a larva. It costs about 150 minerals.

Roach
Has a fast regeneration rate, and is built from the Roach Warren.

The Roach is a very fast moving unit with 90 hp which recovers health quickly. One-on-one, a Roach will generally win in a fight against its enemies, as it regenerates health faster than damage can be delivered when it burrows. As such, sustained damage is required to effectively kill it.

Dustin Browder has confirmed that the roach has a melee attack. A bug in the game showed it as a ranged unit.

It is considered an armored unit.

Ultralisk


Featured in some game builds; now has 4 scythes instead of 2. Costs 6 food. Deals about 70 damage, which is about 7 times stronger than a Hydralisk. Very expensive and powerful units for taking out ground units and buildings. This is the final ground unit in the Zerg technology tree.

Zergling
Zerglings have evolved, affecting such things as their appearance. They have small wings but cannot use them to fly.

They can morph into Banelings and burrow.