In Episode 22 of CEREBRO, Connor and Marvel's X-Office Associate Editor Annalise Bissa hack into the history of Doug Ramsey, a.k.a. Cypher! Killed off in 1988 and not brought back til 2009, the omnilingual mutant is now an integral part of the franchise.
The CEREBRO character file on Cypher begins at 1:26:07.
(Content Advisory: Doug's story includes traumatic mind control. This episode also discusses characters with stories involving unequal power dynamics in romantic relationships, including relationships in which one party is underage, as well as the topic of child sexual abuse.)