|The Alien as a Chestburster as seen in Alien.|
|Last appearance:||Aliens vs. Predator: Requiem|
A Chestburster is a type of Xenomorph offspring that spawns from a living being after the being is attacked by another Xenomorph offspring called a Facehugger. Chestbursters will burst from their victim, and then run and hide until they are grown Xenomorphs.
The Chestburster is the first stage of the life cycle of a typical Xenomorph after a Facehugger hatches from an egg and impregnates it's host with a Chestburster. The Facehugger dies after planting the embryo inside the host's chest and the Chestburster will violently erupt from it's host, causing the host to scream and jerk violently soon before the Chestburster breaks the host's rib cage, resulting in the death of the host. The Chestburster will seek a hiding place until it molts from it's skin and becomes a mature Xenomorph.
The Chestburster species is relatively shy and frightened of larger species. The Chestburster will observe the area around it, on occasion, after bursting from it's host and will usually make a screeching sound after bursting from the host. The Chestburster will seek the nearest and safest place to hide before it molts into a mature Xenomorph.
Deacon · Xenomorph Queen · Xenomorph Drone · Xenomorph Warrior · Chestburster · Facehugger · Runner · Razor Claws · Grid · The Alien · Mantis Xenomorph · Lurker · Newborn Xenomorph · Genetic Xenomorph · Predalien · Boiler · Spitter · Crusher · Praetorian