The Spur is a Kharaa evolution structure unlocked by evolving a Shift Hive. It is an immobile shellfish-like organism with blue tendrils protruding from its shell supported by fleshy tentacles.
The Spur specializes in reactive evolutions, known as Adrenaline and Celerity, which are automatically unlocked when a Spur is created. The reactive evolutions' power increases or decreases with each Spur for a maximum of three times. Reactive evolutions can be purchased in the Evolve Menu, but only one reactive evolution can be active at a time.