X-Factor #10 reveals the victim in The Trial of Magneto, and it's quite a doozyUpdate: 16 hours after X-Factor #10 hit stands, Marvel Comics has revealed the surprise ending to the issue: the Scarlet Witch has been murdered.
While Newsarama generally holds back on spoilers, Marvel has gone all out in revealing the finale of this week's X-Factor #10, which itself is the final issue of the series. The publisher has done so in promotion of a follow-up limited series, X-Men: The Trial of Magneto, which goes into the details and prosecution of Magneto as the suspected murder.
X-Men: The Trial of Magneto #1 variant cover

Along with this spoiler by Marvel Comics, they have revealed a variant cover to X-Men: Trial of Magneto #1 by Mark Brooks. The image is a homage to the classic Renaissance sculpture The Pieta by Michaelangelo. This sculpture has been homaged numerous times in comics, with everything from 1982's The Death of Captain Marvel #1, 1987's Captain Atom #8, 1990's Captain Atom #44, 1993's Harbinger #14, 2002's Deadpool: Funeral for a Freak #3, 2006's Hellblazer #217, 2009's Gen13 #29, and 2016's Civil War II #8.