The Ascaris, introduced in Vor's Prize is a restraining device used by Captain Vor in an attempt to capture a Tenno by making them subservient to him. The device is based off Corpus restraints used to keep robotic proxies obedient, and works by infiltrating the host's nervous system, slowly taking over their physiology until the controller fully commands the victim.
In Vor's Prize, Captain Vor was seen using the Ascaris in an attempt to capture the player. His Ascaris is capable of taking over a Tenno's physiology, their transmission systems, and even shut down the Tenno's own free will, making them obedient.
As this Ascaris is based off Corpus technology, the Corpus-designed Ascaris Negator can be used to remove the restraint. Captain Vor's Ascaris possesses a fail-safe system against tampering however, making the implanted parasite detonate and kill its host unless its controller, Captain Vor, is killed.
In-game, the Ascaris' primary effect is to halve the Tenno's maximum shields, making missions more difficult due to the reduced protection. This effect only activates twice: first when the Tenno rescue Darvo from captivity, and second when the Tenno infiltrate a Grineer Galleon in order to learn of Captain Vor's whereabouts. The Ascaris also permits Vor to make mental contact and communicate with the Tenno.
- Captain Vor also uses an "Omega-variant" Ascaris symbiote to extract information from Excalibur in the second issue of the Ghouls comic. This forces the Lotus to cut the Transference link to the Tenno to prevent Vor from finding out more.
- The Ascaris device currently shares the same appearance as the Grustrag Bolt.
- Ascaris is a genus of parasitic nematodes commonly known to infect humans.