Superhero comics might be built around action, but there are plenty of other elements that make the genre so appealing. Indeed, the best stories typically boast more than a splash of suspense and dash of romance – and best of all, a healthy dose of mystery. From the “mask killer” conspiracy in Watchmen to the secret identity of the Green Goblin in Amazing Spider-Man, some of the most acclaimed comics published by DC and Marvel have featured a compelling conundrum at their core.

While most of the biggest enigmas in comics have long-since been resolved, there’s still a surprising number that have yet to be properly explained. Sure, fans have devised convincing answers to many of these lingering puzzles – and comic book creators themselves occasionally spill the beans off the record – but officially, these mysteries remain unsolved!

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10 Who Was The Second Holiday?

Batman The Long Halloween

Set during the sophomore year of Batman’s career, Batman: The Long Halloween sees the Dark Knight on the trail of Holiday, a serial killer who commits crimes on, well…holidays. It’s a headscratcher that stumps even the Riddler, but in the end, the Caped Crusader deduces that Alberto Falcone – son of Gotham City’s crime boss, Carmine “The Roman” Falcone – is the culprit.

However, it doesn’t end up being such an open and shut case. During Long Halloween’s extended denouement, Two-Face casually discloses that there were actually two Holidays. Batman dismisses this as a lie (although he doesn’t sound totally convinced!), and a private confession by Two-Face’s wife Gilda during the final scene points to her being the other guilty party.

Our guess: As improbable as it seems, Gilda was probably the first Holiday (although as her mental state by the miniseries’ conclusion is fragile at best, we’ll never be 100% sure) before unintentionally passing the baton to Alberto mid-spree.

9 Who Is Earth X’s Daredevil?

The first of two mysteries on this list to emerge out of Marvel’s Earth X miniseries and its subsequent follow-ups, this entry concerns the true identity of Daredevil. See, unlike the mainstream version of ol’ hornhead, the Daredevil of this dystopian alternate reality has never been confirmed – we just know he’s definitely not Matt Murdock.

Several possibilities have been thrown into the mix, including the likes of Wade Wilson and Curt Connors – the civilian alter-egos of Deadpool and the Lizard, respectively – yet Daredevil himself has shot them all down. What’s more, this one-time circus performer has always maintained his mask doesn’t hide a face familiar to comic book readers – but is he telling the truth?

Our guess: It may not be the most exciting explanation, but we’re inclined to believe Daredevil when he says that he was a nobody before gaining superpowers and squeezing into his red spandex.

8 Who Was Behind Dream’s Downfall?

Part of The Sandman’s brilliance lies in how author Neil Gaiman leaves several plot threads and concepts intentionally ambiguous, which has encouraged continued speculation since its 1996 finale. One of the most intriguing open-ended questions in this fantasy series pertains to who really brought about the downfall of its protagonist, Dream.

Ostensibly, former superhero Lyta Hall is to blame – she’s the person responsible for calling down the bloodthirsty Furies on the Lord of Dreams, after all. But a lot happens in the lead up to Dream’s demise that Lyta had zero control over, and the motivations and actions of several of Dream’s enemies – Lucifer, Loki, Puck, and Desire – around this time are murky, to say the least.

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Our guess: Dream himself is ultimately to blame. Desperate to escape his never-ending role as King of Dreams but incapable of shirking his responsibilities, Morpheus directly and indirectly manipulates events to ensure his destruction is inevitable. Gaiman himself has since referred to Morpheus’ exit from the series as “suicide”, essentially confirming this theory.

7 What’s Inside Wolverine’s Box?

return-of-wolverine-2-variant-header

Way back in 1997, Wolverine received a wooden box from interdimensional agent Zoe Culloden, the contents of which readers aren’t privy to. Over the next few issues, we don’t learn anything more concrete about what this curious cube contains – although whatever it is, a revolving door of supervillains all seem to think it’s worth stealing!

Writer Larry Hama’s run on Wolverine wrapped up soon after, and incredibly, the veteran scribe didn’t bother to tie off this particular loose end. Hama has been open about how little forethought he puts into plotting – typically not knowing where a story is going ahead of time – so we’ll probably never find out what Logan’s special delivery was!

Our guess: Frankly, there’s no way of knowing for sure – but considering who sent it, we’re guessing it’s a tool that allows users to travel to (or even alter) different dimensions.

6 What Is Rip Hunter’s Real Name?

Rip Hunter holding up the Supernova and Booster Gold

As you’d expect from a time travelling adventurer, Rip Hunter’s biggest fear is that his enemies will one day use the same technology that makes his exploits possible to erase him from existence. That’s why our hero has gone to great lengths to remove his personal information from the DC Universe’s timestream: to prevent anybody from going back and bumping him off as a baby.

This includes Rip’s very name, which is merely an alias he adopted to conceal his real handle. “Rip” has since been outed as the son of fellow time traveller Booster Gold – which means they likely share the same surname, “Carter”. But that still leaves 50% of this puzzle left to solve!

Our guess: Honestly, we have no idea – there are literally thousands of options to choose from (and that’s a conservative estimate). That said, we wouldn’t be surprised if Rip was named after Booster’s dad, which would make him “Jon Carter”.

5 How Did Earth X’s Gambit Kick The Bucket?

The second Earth X-centric entry on this list, this time dealing with how Gambit perished in this alternate reality. When Earth’s new Watcher, the robot superhero X-51, reviewed the records of his all-seeing predecessor, he learned that Remy LeBeau lost his life after kissing Rogue. This makes sense, since Rogue’s uncontrollable absorbing powers can easily prove fatal to those who make contact with her skin.

But Gambit’s X-Men teammate Beast later claims that Remy ran afoul of a hitman, clearing Rogue of any involvement. Frustratingly, series co-creators Jim Krueger and Alex Ross planned to address this apparent continuity error in Tales of Earth X, however that miniseries was scrapped due to Earth X sequel Paradise X’s poor sales.

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Our guess: Although the Watcher’s records should be more accurate than pretty much anyone else’s, Beast’s account is considerably more detailed – so either both stories are somehow true, or Krueger and Ross changed their minds somewhere along the line.

4 What’s The Deal With The Three Jokers?

Three Jokers

One of many jaw-dropping revelations to come out of 2016’s DC Universe: Rebirth one-shot was the bombshell that the Joker is actually three separate guys operating under the same identity. This calls into question virtually everything we know about Batman’s most iconic foe – not to mention the Dark Knight’s reputation as “The World’s Greatest Detective” – and we’re still waiting for answers.

Writer/artist team Geoff Johns and Jason Fabok have promised that Batman: The Three Jokers will make everything clear, but the three-part series still doesn’t have a release date. Until then, all we know is that the trio of villains referenced in its title represent specific versions of the character: the Joker as he first appeared in 1939, his classic 1960s incarnation, and the iteration seen in Batman: The Killing Joke.

Our guess: It’s hard to see how these three individuals fit together – but it seems likely that they supplanted each other at different stages of Batman’s career, possibly even eliminating their direct predecessors first!

3 Who The Heck Was Wearing The F.A.C.A.D.E. Armor?

FACADE vs. Spider-Man

The Full Acclimation Combat And Defence Explo-skeleton (or F.A.C.A.D.E.) was a suit of cutting edge body armor that featured in the Spider-Man comics of the mid-90s. So far, so boring – but what makes the F.A.C.A.D.E. armor fascinating to this day is that we’ve never discovered who was wearing it.

Seriously: this plot thread has been left dangling so long, it’s become something of a running gang over the past few years! The three main suspects are Daily Bugle photographer Cole Cooper, wealthy industrialist Archer Bryce and one-time astronaut (and son of J. Jonah Jameson), John Jameson. The clues available to us appear to rule out Cooper, but Jameson and Bryce remain viable contenders.

Our guess: The smart money is on Archer Bryce – if for no other reason than it’s the neatest solution – although unveiling a “nice guy” character like Jameson as the villain would make for a more satisfying twist.

2 What’s Really Beyond The Source Wall?

Shattered Source Wall

The Source Wall is a cosmic (yet very much tangible) barrier that exists at the furthermost edges of the DC multiverse. With rare exception, the Wall has proven to be unbreachable – almost everyone who has tried, no matter how powerful, has wound up imprisoned along its surface, instead. As a result, it’s never been conclusively established exactly what lies on the other side of the Source Wall.

Initially, this super-sized fence was said to contain the Source, the consciousness of the DC Universe itself. This was later contradicted by stories that described the realm beyond the Wall as the Bleed between alternate universes, a quasi-heaven for the New Gods, a reservoir for mystical emotion-based energy, a jail for nigh-omnipotent baddie Perpetua and more. So…which of these is true?

Our guess: This is going to sound like a cop-out, but we think that all of these things (plus a whole bunch of other stuff, as well) are barricaded behind the Source Wall. Since the Wall is meant to symbolise the limits of mortal knowledge, it stands to reason that anything that exists outside its bounds would constitute a mind-bending mash-up of conflicting concepts.

1 Who (Or What) Was Inside Scarlet Witch’s “Closet”?

Scarlet Witch

Following the House of M crossover event, Scarlet Witch is left addled by partial amnesia – but then, rewriting reality more than once will do that to a person. Eventually, her Avengers pal Hawkeye tracks Wanda down to a tiny European village, to the small apartment she claims to share with her elderly Aunt Agatha.

This strikes Hawkeye as more than a little disconcerting, as Scarlet Witch’s deceased mentor was also an older lady called Agatha Harkness. Later, the Marvel Universe’s premier archer goes to investigate Agatha’s room – referred to by fans as her “closet”, due to its modest size – only to seemingly be prevented from doing so by Wanda’s reality warping abilities. Because of this, neither Hawkeye (nor readers) ever learned who (or what) was on the other side of those doors!

Our guess: Well, it could just be Agatha, especially since she’s shown up in spirit form subsequently. Yet this seems a bit too pedestrian, so our theory is Wanda’s closet is home to an artificial entity created by her subconscious to distract her, keeping her powers on a leash in the process.

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