A Hybrid is an entity that represents the first step in the Cylon evolution from pure machines to organic beings (Razor). They serve as the central computer inside a basestar (Torn).
The Hybrids resemble human beings inside an immersion tank similar to a Cylon rebirthing tank. However, they are not humanoid Cylons, but another type of Cylon, similar to the autonomous bio-mechanical Raiders <1>, specially constructed as living computers that manage the autonomous functions of the basestar, including navigation, propulsion (especially faster-than-light) and climate control. The Hybrids are so integrated into the basestar's functionality that they are, for all practical purposes, the basestar. The Hybrids may also be in contact with the Centurions and possibly the Raiders.
The First Hybrid is the precursor to the modern Cylon Hybrids, and is the first step in their evolution from pure machines to organic beings.
There are references in the Cylon databases to this prototype, considered a failed experiment and unaccounted for. William Adama stumbles across the birthplace of the First Hybrid at the end of the first Cylon War.
" . . . Soon there will be four, glorious in awakening. Struggling with the knowledge of their true selves. The pain of revelation bringing new clarity.
And in the midst of confusion, he will find her, enemies brought together by impossible longing, enemies now joined as one. The way forward, at once unthinkable, yet inevitable. And the fifth still in shadow, will claw toward the light, hungering for redemption that will only come in the howl of terrible suffering. I can see them all. The seven now six self-described machines, machines who believe themselves without sin. But in time, it is sin that will consume them. They will know enmity, bitterness,
the wrenching agony of the one splintering into the many and then they will join the promised land, gathered on the wings of an
angel. Not an end, but a beginning....
Kara Thrace will lead the human race to its end. She is the herald of the apocalypse, the harbinger of death. They must not follow her. As my own existence comes to a close only to begin anew in ways uncertain. All this has happened before and will happen again. Again, again. Again. Again. "