Spinners are the Chimera's recent alternative of infecting human hosts and creating new Chimeran strains in response to the aftermath of Operation Overstrike, in which the Carrier strain was compromised and exterminated by Dr. Claude Bouchard's serum, lessening the Chimera's need of Conversion Centers. Spinners are released from Spires, just like Crawlers, and move on to capture humans and weave them into cocoons, hence the name. From here, hosts are converted into whatever strain is in short supply and/or is needed.
It is never particularly clear how such small creatures can overpower and restrain able-bodied adults; they are mentioned as being as unstoppable as Crawlers, but do not seem to be deployed in overwhelming numbers. Indeed, at one point Henry Stillman describes Spinners somehow overturning a moving vehicle, something that the creatures would seem incapable of doing. How Spinners actually "work" remains a mystery.
In Resistance: The Gathering Storm, it is depicted that Spires contained in yellowish softball-sized eggs that hatch into thousands of infant Spinners, which then 'morph' into cat-sized individuals. When they find an individual human, they will spray a pinkish brown webbing on them. This chrysalis rapidly hardens, after which the Spinners will carry it away. It is mentioned that Spinners are apparently capable of stinging, and that they are equipped with fangs and hollow barbs through which chemicals can be injected into victims, resulting in uncontrollable thrashing. This chemical could possibly be used in the process of turning a human (and other organisms) into new Chimera, such as Grims or Hybrids. It has also been stated in Resistance: A Hole in the Sky that Spinners need to bite their victim in order to incapacitate them prior to spinning a cocoon around them.
A strain of Chimera known as the Mother Spinner is seemingly some sort of "queen" to these Chimera, though the only Mother Spinner encountered in the series did not in any way associate itself with them. This strain is most likely not created from human hosts, and instead may be created similarly to the Leapers of Resistance: Fall of Man.
During the campaign, Nathan Hale encountered many Spinners - though only one or two at a time - but they never attack and usually run away from him, presumably because they sense that Hale is already infected. Killing 30 Spinners throughout the campaign earns the player the Silver Snipe Hunt Trophy.
Although Spinners do not play as large a role as they did in Resistance 2, Joseph Capelli does encounter some in the underground tunnels in New York City in "Commitment" and one in "The Pit". It is not clear if Spinners are Feral Chimera or not, given that the Chimera had no need for converting humans. Spinners, strangely, do not attack Joseph (given that he is cured of the Chimeran virus), and the reason for this remains unknown.
- In the Idaho level, inside the dog kennel of the second house's yard, is a small Grim cocoon. This implies that Spinners will also attack creatures apart from humans, such as dogs. Upon destroying the cocoon, a dead Grim will appear; this indicates that the organic material inside the pod is broken down and restructured to form the Grim, rather than just being altered from the existing form. While this could be intended to show a human child taking shelter in the kennel, this interpretation leaves no explanation of what happened to the dog.
- The Spinners are referenced by The Chrysalis to James Grayson at the end of Resistance: Retribution, foreshadowing the Chimera's change in strategy, as seen in Resistance 2.
- Only Grims are seen emerging from the cocoons in any of the games, though Resistance: A Hole in the Sky shows a Menial hatching from one. It is not clear how the metal parts of a Menial would be created from organic materials, and this is most likely an error.