Tyranids are seen as one of the gravest threats to the entire Galaxy. They seek only to consume all organic life and they cannot be reasoned or bargained with or deterred in this singular quest. Worse still for the Galaxy, thus far the Tyranid Hive Fleets that have been encountered are merely the furthest stretched tendril of the main invasion fleet that is still travelling in the void of space. When the main fleet emerges from the void, it is unknown if any race will be able to stand against them.