Today, we look at the 1996 reveal that Professor X was secretly Onslaught, turning the X-Men's world upside down!.

This is "Look Back," where every four weeks of a month, I will spotlight a single issue of a comic book that came out in the past and talk about that issue (often in terms of a larger scale, like the series overall, etc.). Each spotlight will be a look at a comic book from a different year that came out the same month X amount of years ago. The first spotlight of the month looks at a book that came out this month ten years ago. The second spotlight looks at a book that came out this month 25 years ago. The third spotlight looks at a book that came out this month 50 years ago. The fourth spotlight looks at a book that came out this month 75 years ago. The occasional fifth week (we look at weeks broadly, so if a month has either five Sundays or five Saturdays, it counts as having a fifth week) looks at books from 20/30/40/60/70/80 years ago.

We're a bit behind, so we're still looking at May books, specifically the May 1996 X-Men comics, Uncanny X-Men #334 and X-Men #54, which revealed the identity of Onslaught.

Following the end of Age of Apocalypse, the world of the X-Men was thrown for a bit of a loop when Juggernaut was battered mercilessly by a mysterious entity only known as "Onslaught." The X-Men mostly just kept living their lives for the next few months, but Onslaught kept popping up here and there until Jean Grey was actually psychically kidnapped in X-Men #53 by Onslaught himself, who wanted Jean to come join him in his mysterious war. She obviously said no, but he then showed her the inner thoughts of Professor Xavier and in a clever bit, Mark Waid worked in a thought bubble from an early issue of X-Men where Xavier pined for Jean (him being in a wheelchair was the only reason why he thought it couldn't work). Jean is weirded out, but she obviously doesn't agree to work with Onslaught.

A frazzled Jean returns to the X-Mansion and she meets up with Juggernaut, who has a psychic block preventing him from remembering who Onslaught is.

Meanwhile, Professor Xavier is being really weird around the Mansion. Cannonball was feeling down on himself after a recent mission with Wolverine and instead of comforting the newest member of the team, Xavier basically tells him to suck it up and shut up. Xavier then unleashes a vicious verbal attack on Cyclops, but Cyclops is able to look past it. At the end of the issue (which was by Scott Lobdell, Joe Madureira and Tim Townsend), Jean Grey brings Juggernaut to the secret basement lair at the X-Mansion that Xavier had used decades earlier to fake his death by cutting himself off from the rest of the world.

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This brings us to X-Men #54 (by Mark Waid, Andy Kubert and Dan Panosian)...

Juggernaut gets in some nice bits where he points out that Jean was the only person that Xavier told about faking his death back in the day. This definitely picks at the gnawing unease that Jean was feeling from what Onslaught showed her in the previous issue...

Meanwhile, the X-Men all know that Juggernaut is loose in the X-Mansion SOMEwhere, so they are all looking for him an Cyclops, naturally, is freaked out by Jean suddenly cutting off their psychic-link.

Finally, Jean cracks the psychic block on Juggernaut's mind and she freaks the heck out, as knowing who Onslaught is is not good news. She awesomely just tells Juggernaut to run as far as he can, as she knows Onslaught does not mean well for him...

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Juggernaut heads to his step-brother Charles Xavier's office, to find it is shambles. He is then attacked by Onslaught, he taunts the Juggernaut...

And then the big reveal...Onslaught IS Charles Xavier! Dun dun dunnnnnnnnnnnnn! Now, just as soon as this twist was introduced, we very quickly had it all sort of wiped away as all sorts of conditions were placed on it. You know, it wasn't Xavier, it was Xavier's mind merged with the bad parts of Magneto's mind and stuff like that and sure, fair enough, you want to keep Xavier as a working character, after all...

But for at least this one shining moment, Xavier was a villain and the X-Men's world was thrown into a chaos that they had not seen since the earliest days of the Mutant Massacre, a real sense of unease that they truly wouldn't totally recover from until perhaps Grant Morrison's run on X-Men books.

Amusingly, Onslaught was also used to retroactively solve the mystery of the "X-Traitor" from Jim Lee and WHilce Portacio's X-Men run. We now know that the "X-Traitor" was Xavier himself! Clever stuff! It also gave Bishop one of his best moments he has had in his comic book career, when he finds a away to save the X-Men from Xavier, but that's all another month!

If you folks have any suggestions for August (or any other later months) 2011, 1996, 1971 and 1946 comic books for me to spotlight, drop me a line at brianc@cbr.com! Here is the guide, though, for the cover dates of books so that you can make suggestions for books that actually came out in the correct month. Generally speaking, the traditional amount of time between the cover date and the release date of a comic book throughout most of comic history has been two months (it was three months at times, but not during the times we're discussing here). So the comic books will have a cover date that is two months ahead of the actual release date (so October for a book that came out in August). Obviously, it is easier to tell when a book from 10 years ago was released, since there was internet coverage of books back then.

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