Chestburster

The Chestburster is a Xenomorph larvae. It's egg is laid in the host's bronchial tubes by a Facehugger, where it hatches. It then burrows for the host's aorta (major artery in the heart), where it feeds on absorbed nutrients and white blood cells. After about an hour or two, it lets go, and begins swimming about in the host's body, causing mild discomfort. Then, it finds the sternum, and starts chewing. This causes the victim geat pain, shock, and blood loss. Then, true to it's namesake, it pops out, and finds a nursery or chicken coop, or, less messy, a food locker, something with a large amount of helpless meat. It's carapace has yet to harden, and is a dull grey fleshy hide. Depending on the host, it will grow to become a Drone (human, black carapace (standard Xenomorph)), PredAlien (Yautja, yellowish-green partial hide), or Runner (any given quadruped, red hide). Genetic alteration causes it to split into identical twins after escape from a human or quadruped (AVP Extinction).

An embryo implanted in a pregnant woman will feed directly on the baby, and will erupt from the stomach of the woman. (Avp:R)

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