Form

Forms were different physical stages assumed by the Forerunners over the course of a lifetime. The Forerunners were able to mutate into various forms through an artificially-induced transformation. Manipular, or Form Zero, was the first and simplest form, assumed by Forerunners at birth. It was noted that Manipulars bore a striking resemblance to humans; however, this would change with higher forms. Higher forms also lacked some of the natural abilities possessed by Manipulars, including the ability to smile.

In each mutation, a Forerunner would acquire the genetic imprint of their mentor, typically the individual's father. However, warriors sometimes performed mutations in battlefield conditions, where the imprint would be supplied by one's commander. The form one would mutate into was dictated by their rate, as well as the person who performed the mutation. For example, Warrior-Servant were noticeably taller, more rugged and more muscular than Builders, whose forms were more refined. Aside outward appearances, there were also differences in mental and neurological functions. After a mutation, small changes or corrections could be made, but these were mostly cosmetic.

By roughly 100,000 BCE, a new, more natural mutation pattern had been developed. Instead of being subjected to multiple mutations over several centuries, one would undergo a series of changes over a single year. This would result in less inherent physical or mental distortions. Most Forerunners mutated according to this new pattern came from Builder families, with a few Warrior-Servants among them.

List of appearances

 * Halo: Cryptum