A surveillance bot used by both the Syndicate and WATI. When deactivated a Spider resembles a small sphere roughly the size of a football, but when active it breaks up into a quadrupedic form. They act as small security bots, and can either remain stationary, using their sensitive sound and motion detectors, or locate intruders by patrolling on foot and sweeping the area with a light sensor.When threatened or upon detecting an intruder, Spiders use a short burst of electricity to 'fry' their enemy - this is enough to destroy electronic equipment like Watillas or actually kill an adult human. Spiders themselves are not shielded against this attack, and Zoë is able to use a spare Spider in the WATI laboratories to destroy another that roams the corridors. They can also be lured with noise, and are vulnerable to short-circuiting by running water as Zoë is able to discover in Reza's apartment. Liv identifies the spider in Reza's flat as one of the S-850 series manufactured by Asad Robotics; she knows the EYE ordered several thousands of them a few years back. She is able to give Zoë a hack to disable the thing, if she can creep close enough to see the logo.
As part of their security duties, Spiders can also carry basic clearance codes so they can access protected areas safely, and transmit these codes between themselves. Zoë's Spider, once it fries its twin, downloads its clearance and uses it to deactivate the grid in the security office.
Not surprisingly, given her frequent run-ins with them Zoë now has a distinct dislike of Spiders.