5 Things We Need to See in the Arrowverse's Upcoming 'True' Crossover

Last December's #CWInvasion was a huge hit. The CW successfully brought together four shows — #Arrow, #TheFlash, #LegendsOfTomorrow and #Supergirl — for four nights of amazing superhero action.

But despite the success of this crossover event, there was still that nagging feeling that it wasn't quite the four-way crossover that we were promised; really, it was a crossover between Arrow, The Flash and Legends of Tomorrow — with a guest appearance from Supergirl.

Even though all of the marketing promoted a four-show event, many viewers felt short-changed by the lack of involvement from Supergirl's supporting cast — in actuality, the crossover element was the final 90 seconds or so of the episode. Thankfully, Kara went on to play an essential part in helping the Arrowverse heroes defeat the Dominators, so there was plenty of action in that sense.

At a recent CW press event earlier this week, Arrowverse executive producer Andrew Kriesberg offered us an amazing tease:

"Next year, we’re hoping to do a true four-way crossover"

He also explained that Supergirl moving to The CW was the main reason behind the other characters' lack of availability. Essentially, because they weren't sure where the show was going to be broadcast, they couldn't make any solid plans about incorporating it into the crossover.

But now that the dust has settled and everyone is certain that Supergirl will be a part of the Arrowverse next year, plans can be made to fully integrate Kara's supporting cast into this year's event. So just what do we want to see, and what new possibilities does this offer? Here are five possibilities.

1. Winn Joins The Brain Trust

With the freedom offered by the producers knowing their plans for the characters, we can finally see some of Supergirl's supporting cast follow her across to Earth-1. We'll be able to see Alex meet the agents from ARGUS, J'onn J'onzz join forces with the Legends (more on him in a minute) and, most excitingly, Winn joining forces with the Arrowverse's tech support.

In Season 1 of Supergirl, Winn was the IT guy at Catco who just happened to be handy with a sewing machine as well as mad hacking skills. Since the move to Vancouver, he's changed jobs to working alongside Alex and J'onn at the DEO. This has allowed him to shine as he has more than proved his capabilities in creating new gadgets to defeat villains while also using his hacking skills to track down their lairs.

In a four-way crossover, we would be able to see Winn interacting with the likes of Felicity and Cisco to create even more amazing gadgets capable of defeating any foe. Cisco loves a film reference and we all know that Winn is a Star Trek fan so they'd clearly get on, while Felicity would probably enjoy having someone else to help with the technical side of superhero-ing.

2. Team Arrow In National City

Even though Arrow is the show we have to thank for the current glut of DC superhero shows on TV, they've never actually left Earth-1. Don't get me wrong, this makes total sense because of the grounded nature of the show — but because of the fantastical nature of the supporting shows, it seems strange that they've never been involved in any time-traveling or dimension-hopping adventures.

Maybe this year's crossover event could take place entirely on Supergirl's Earth-38, meaning that Team Flash, the Legends and Team Arrow all have to hop across dimensions. While Team Flash is used to traveling the multiverse, and the Legends have completely lost track of what day it is thanks to travelling through time, Team Arrow's reactions to a new universe would be interesting to see.

If there's one character we can rely on to give us a brilliant reaction to the new universe, it's John Diggle. His reactions to witnessing Barry's superpowers for the first time are absolutely hilarious, so just imagine seeing Diggle in the Alien Bar that the Supergirl cast visit frequently. He played it really cool when he first met Kara, but a bar full of aliens would be a sight to behold.

3. J'onn J'onzz Meets The Arrowverse

Another member of Supergirl's supporting players who would be very useful in the event of a superhero team-up would be J'onn J'onzz, the Martian Manhunter. Not only because of his superpowers — his tactical knowledge from his time running the DEO would be a great help. He frequently helps Kara defeat her enemies, so why wouldn't he be up for helping the rest of the Arrowverse heroes?

We've seen Martian Manhunter interact with the other heroes in the Superhero Fight Club 2.0 trailer, but we can probably say that's not canon and was purely made as a fun trailer to get the fans excited.

However, he's proven time and again that he's a useful asset to Supergirl, so it would be great to see him interact with the other heroes (though I doubt he'd get along with Mick Rory!). Diggle's reaction to seeing a real Martian could potentially be even better than it was in the trailer.

4. More Banter Between The Heroes

It's fair to say that saving the world from an alien armada is an excellent team-building exercise, so I'd love to see the heroes having a great time with one another. Potentially, they could find themselves overconfident of success at the beginning of the next crossover; underestimating the threat, the heroes regroup and decide they need help — this is where Kara calls for reinforcements.

One of the brilliant aspects of the #HeroesVsAliens crossover was the combinations of characters that were brought together. Rather than simply stick with their own individual teams, the characters all mixed in together. This was particularly obvious when Cisco entered the Arrow Bunker to help hack into some alien technology (as you do) and then in the following episode when Felicity and Cisco joined the Legends in travelling back in time.

With a huge cast to play with, there's almost limitless combinations of characters that could be seen. I, for one, would be very interested to see Mick Rory and Oliver Queen having a drink together after realizing that they're just two normal men with a flamethrower and a bow and arrow in a team containing the Flash and Supergirl.

5. A Truly Compelling Villain

If there's one thing that Legends of Tomorrow is demonstrating, it's that the Arrowverse already has some fantastic villains in its shows. With the current incarnation of the Legion of Doom, they've brought together three of the biggest villains in the history of the Arrowverse — Damien Darhk, Malcolm Merlyn and the Reverse Flash — to create a truly brilliant villain team (and that's before Captain Cold joins the Legion!).

Rather than a new threat, perhaps the crossover's villains can be someone we've already seen. There's plenty of villains to choose from: Slade Wilson would be an excellent choice in my opinion, Grodd would be another — though they're just two of them!

Everyone has their favorite villain, so we all will have different ideas of who it could be. What's important, though, is that the villains are compelling enough and hold a strong enough threat that the entire Arrowverse need to combine their forces to stop them!

There are so many exciting possibilities with a four-show crossover — and if it comes off, it will be a triumph. As much as the previous crossover was billed as a four-way crossover, it wasn't really. After the confirmation that Supergirl's supporting cast will be involved in this year's crossover there are certainly exciting times ahead!