No one on the XCOM/NERV side really knows. The Soviets weren't involved in the GEHIRN/SEELE/NERV complex and never participated in the Marduk program. As for Защитник, even when they were working closely together with NERV's people in Halifax, Dr. Kirishatov's team kept certain aspects of its inner workings close to the vest, including the control system. It's known to involve an R-grade military neural interface, like the MiG-31F and XCOM's advanced Raiden-DX and Firestorm-class interceptors (and the Archangelions), but they never revealed whether the particular psionic resonance peculiar to Evangelion pilots is required to operate it.

--G.
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Benjamin D. Hutchins, Co-Founder, Editor-in-Chief, & Forum Mod
Eyrie Productions, Unlimited http://www.eyrie-productions.com/
zgryphon at that email service Google has
Ceterum censeo Carthaginem esse delendam.