This is, by far, the biggest crossover the Arrow-verse has ever pulled off. Five hours of TV, an unfathomable number of DC Comics superheroes making appearances, and an entire multiverse facing destruction. Warning: The following contains spoilers for the first three hours of the Crisis on Infinite Earths crossover event. If you haven't watched and don't want to be spoiled, look away now.

The first three hours alone are littered with Easter eggs and references to not only newly-discovered corners of the Arrow-verse, but old DC TV shows and movies, as well as nods to the comics that are responsible for all of these properties. There are so many, it would be easy to miss a handful of them. Luckily, you don't have to worry about that.

We've paid very close attention to all three hours of the crossover so far, documenting all of the Easter eggs for you. Take a look at them all below while you prepare for the final two episodes when they air January 14 on The CW.

1. What a headline

The first thing we see in Crisis is a glimpse at Gotham City on Earth-89, otherwise known as the Gotham that Tim Burton's Batman films exist in. Batman was released in 1989. Get it? It's hard to see the date on this newspaper, but given that Joker (Jack Nicholson) died in the 1989 film, either this is the next day or that Gotham is being hassled by a successor to the original Joker. Either way, we want to know more. Interestingly, the Gotham City Gazette is not the newspaper featured in Batman (1989). In that film, it was the Gotham Globe.

2. Oh, hey Knox

And who better to serve as an introduction to this version of Gotham than Alexander Knox, the journalist played by Robert Wuhl in that Batman film.

3. Meanwhile, on a streaming Earth

After jumping to another Earth, we are greeted by Hawk (Alan Ritchson) from the DC Universe original series, Titans. His appearance wraps that show's continuity into the larger Arrow-verse, even if we only see him briefly.

4. But that's not all

We also see a brief glimpse of Jason Todd (Curran Walters) in his Robin gear, as he and Hawk face down the destruction of their Earth.

5. And over on Earth-X

We also catch a glimpse of The Ray (Russell Tovey), who was first introduced as a hero in the 2017 Arrow-verse crossover, Crisis on Earth-X.

6. Holy Robin, Batman

We knew this cameo appearance was coming, given that it was teased at Comic-Con. Still, seeing Burt Ward--the original live-action Robin--appearing in the Arrow-verse is a special treat. He even has a typically outlandish Robin line, exclaiming, "Holy crimson skies of death!"

7. This technically counts as two Easter eggs

Look, kids. It's Wil Wheaton. The former Star Trek: The Next Generation star has done voice work in a number of DC animated shows and movies, but this is his first live-action appearance on a DC project. What's more, the sign he's carrying is a replica of one that appears in Superman II.

8. Superman does dirty diapers

Our first glimpse as Superman (Tyler Hoechlin) as a Superdad is a funny one, in which he takes care of a super dirty diaper. Not only is this a nod to Superman being a dad in the comics, but it's also a look at what the potential Superman and Lois Lane spin-off that's being developed could be like.

9. Quantum towers are not pretty

Yes, the quantum towers are pulled from the comics. They were constructed by the Monitor (LaMonica Garrett) to slow down the progress of the quantum wave destroying the multiverse.

10. The next Green Arrow

We know that Arrow is coming to an end and a female-centric spin-off is in the works. It looks like when all is said and done, Mia Smoak (Katherine McNamara) will be the next Green Arrow, based on the costume her dad had made for her.

11. Yet another Wells

Tom Cavanagh rarely plays the same version of Harrison Wells for more than a season. This time, though, even that's been cut down. His latest incarnation--Nash--has now become Pariah. In addition to the new name and fancy costume, this character--which also appeared in the Crisis comics--can travel between Earths to collect heroes.

12. The death of the Green Arrow

Sure, Oliver's only "kind of dead" when all is said and done, but the death of the Green Arrow is another story twist pulled from the pages of the Crisis comic book. In the miniseries, Earth-2's Green Arrow--the Golden Age version of the hero--died during Crisis.

13. Luke Fox returns to his comic book roots

On Batwoman, Luke Fox (Camrus Johnson) is essentially Kate Kane's (Ruby Rose) nerdy Alfred. He's portrayed a bit differently in the comics. On Earth-99, though, Luke resembles the version comics fans should recognize, as the nerdy persona is nowhere to be seen.

14. Batman's gotten old

While we see Bruce Wayne (Kevin Conroy) in an exosuit that definitely conjures images of the character's appearance in Kingdom Come, that's not who this particular Batman is. Instead, this Bruce takes a cue from The Dark Knight Returns, where Batman has turned cold and killed off several of his enemies.

15. The Death of Superman

This quick glimpse at a TV recreates imagery from the Death of Superman comic. Thankfully, the Arrow-verse's primary Superman is fine.

16. Hey Constantine

Yes, John Constantine is a regular character on Legends of Tomorrow. However, he's also a character that ties yet another DC show--the defunct Constantine on NBC--into the Arrow-verse.

17. Somebody save us

Talk about a blast from the past. Tom Welling reprising his role of Clark Kent from Smallville was a special moment. Even more interesting was learning he gave up his powers to live a normal life with his wife Lois (Erica Durance) and their kids.

18. Speaking of Lois

The Smallville-set scene also provided an appearance by Durance as Lois Lane.

19. Yet another Clark Kent

Hey, he looks familiar. Not only does Brandon Routh star on Legends of Tomorrow, but he also played the Man of Steel once upon a time in Superman Returns. Thanks to Crisis, he gets to suit up as Clark Kent once more, but this time a different take on the character.

20. Anyway, about those people Batman killed

Naturally, Bruce Wayne keeps trophies of the enemies he's killed. The first we see is a Joker card. At long last, the Clown Prince of Crime finally got what was coming to him.

21. Two-for-one

We then see a shot of Riddler's cane and what looks like Mr. Freeze's snow globe, meaning Batman has definitely killed them both off.

22. But not this

We also see Clark Kent's glasses as it's revealed that Batman actually killed Superman on this Earth.

23. Lots more dead people

Back on the Earth of Routh's Clark Kent--which resembles the Kingdom Come storyline from the comics--we see all those the Man of Steel has lost, including Perry White, Jimmy Olsen, and his wife, Lois Lane.

24. Thanks to the Joker, of course

Clark reveals that it was a psychopath from Gotham that played a "prank" on the Daily Planet because they weren't writing about him enough.

25. And Kingdom Come Superman was born

At that point, this Clark puts on his Superman costume, revealing the iconic Kingdom Come design that was previously teased.

26. Superman vs. Superman

It's not Batman v Superman. It's actually better as Routh's Superman, under Lex Luthor's control, attempts to destroy Hoechlin's Superman.

27. Another familiar face

The Legends have plenty of experience with Jonah Hex, but not this version. Johnathon Schaech reprises his role in the Arrow-verse, playing another Earth's Hex.

28. Another super baby

We learn that Routh's Superman either has or had a son named Jason. This is a nod to Superman Returns, where it's hinted that the son of Lois Lane--Jason White--is actually Superman's child.

29. Enter the Anti-Monitor

At long last, we meet the Monitor's arch-nemesis--the Anti-Monitor. It's a terrible name and, yes, it's pulled from the comics.

30. A true Bird of Prey

It may have only lasted 13 episodes, but it's exciting to see Ashley Scott reprise her Birds of Prey role as Huntress. Like most of the cameos, though, it ends quickly.

31. The All-Star Squadron

Ralph (Hartley Sawyer) is justified in being blown away by seeing all of these superheroes assembled. The All-Star Squadron he mentions, though, is an actual team of superheroes. They were introduced in a 1981 issue of Justice League of America and have included a long list of different heroes over the years.

32. Who is Ryan Choi

Believe it or not, Ryan Choi is a character in DC Comics mythology. In fact, as in Crisis, he's a big fan of Ray Palmer in the comics. In addition to that, though, he also becomes the Atom in the comics.

33. The devil, you say

Everyone's crossing over this year. Even Lucifer (Tom Ellis), from Netflix's Lucifer, made a quick appearance, pointing Constantine in the right direction to track down Oliver's soul.

34. Welcome back, Barry

John Wesley Shipp returned as the Flash from Earth-90--otherwise known as the Flash from the 1990 TV series. It's always fun to see that old suit.

35. Black Lightning's back

For the first time, Black Lightning was officially acknowledged as part of the Arrow-verse. Jefferson Pierce (Cress Williams) arrived to help out the rest of the heroes and learned that his Earth was wiped out by the anti-matter wave.

36. Batwoman v Supergirl

Thankfully, this didn't turn into an actual fight. Still, seeing these two come face-to-face, ready to battle, was a special moment that hopefully gets explored in the future.

37. A nod to Gail Simone

Ryan Choi was co-created by Gail Simone. With that in mind, it's nice to hear the prolific writer get a small nod with Choi's daughter being names Simone.

38. Flash vanishes in Crisis

It's been promised since The Flash first premiered on The CW. In the end, though, it wasn't Earth-1's Barry that was destroyed in the Crisis on Infinite Earths. Instead, it was Earth-90's.

39. Poor Tina

Before his demise, though, Earth-90's Barry flashed back to a moment with the woman he loved, Tina (Amanda Pays), from the original Flash series.

40. The Spectre

While tracking down Oliver's soul in purgatory, Constantine and company happen upon Jim Corrigan (Stephen Lobo), the Spectre. He wants Oliver to become a Spectre, rather than being resurrected. It's interesting to note--which Constantine does--that this is not the Corrigan that John knows. On NBC's Constantine, the role was played by Emmett J. Scanlan.

41. The Vanishing Point

The place where our heroes are sent to is pulled right from the comics. The Vanishing Point exists in a dimension outside of the time/space continuum.

42. A Crisis reversal

This shot of Supergirl (Melissa Benoist) and Superman (Routh) puts an interesting spin on the cover of the Crisis on Infinite Earths comics. On the cover, Superman is holding a dead Supergirl.