The trailer for the epic Arrowverse crossover, Crisis on Infinite Earths, is here. Here are the five major takeaways from the promo.

It’s the event that we’ve been waiting all year for. Crisis on Infinite Earths will begin at the weekend, and we now have a promo to see what to expect. Everyone is joining together to prevent the destruction of every single world, and it’s all taking place on Earth 38. It means the collection of superheroes from everywhere and that opens a crossover for many different DC shows.

The Crisis on Infinite Earths promo has dropped. We can break it down to figure out five important takeaways from the Arrowverse crossover. Are you ready?

Before we get into the breakdown, you’ll want to see the promo. Here’s a sneak of what’s to come.

5. Multiverses coming together

We knew that the multiverses would come together, but not how or why. The trailer gives us a hint at the reason for it. Across the universes are seven heroes who will form the team to help save the worlds. Supergirl‘s Superman is heading off to the world of Smallville, while The Flash is heading to the world of Black Lightning. We haven’t seen Brandon Routh’s Superman yet, but we know he’ll turn up somewhere along the way. Three Superman iterations in one crossover is going to be epic.

And that’s not all. Batman is back. Well, Bruce Wayne is finally being introduced and things aren’t looking great. What’s happened to him and can he fight with the rest of the heroes?

What’s clear, though, is that everyone will have a part to play. I do get the feeling that it might get a little messy with so many characters, but with five episodes to tell this story, there is some hope.

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4. Oliver isn’t letting people die in Crisis on Infinite Earths

At the very end, The Monitor tells Oliver that it’s time. The anti-matter is going to destroy Earth 38. However, the planet hasn’t been fully evacuated yet.

Oliver, in hero mode, makes it very clear that he’s not leaving until the entire planet has been evacuated. He may be fated to die, but he’s not letting anyone else die as well. He’ll make sure he’s there until the very end, until everyone is safe. Is this actually all a test from The Monitor again and the move he wants to see Oliver make?

3. Supergirl and Batwoman team up again

While there are various teamups, one of the most exciting is going to be Supergirl and Batwoman. And they will team up together as they go in search for Bruce Wayne.

During the Arrowverse crossover of 2018 when Batwoman was introduced, we got to see the type of teamup the two female heroes could offer. They really are the World’s Finest and it was that hint that we need to see more of them on screen together. Fortunately, the writers all agree and that’s what we’ll see during the week.

2. Grief needs to be set aside

Poor, Kara. She has just watched Argo disappear, and now she needs to jump straight into Crisis on Infinite Earths. There’s no time to grieve right now. To make matters worse for her, this fight it taking place on Earth 38; her world. Her own people are being put at risk in the fight.

Grief has to be put aside right now. Supergirl isn’t the only one grieving, but she does tend to take things more to heart than others. She’s full of empathy and that’s what makes her such a great hero. How will she react as she continues in the fight while trying to deal with loss?

1. This is just the beginning

I don’t think that this is the entire crossover. Honestly, this is just a hint of things to come in the first episode or two. There’s so much more in the five-episode crossover. Will we move worlds? Will we see Earth 38 destroyed? Could this mean that everyone ends up on the same world in some way, making crossovers much easier in the future?

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What do you think of the Crisis on Infinite Earths trailer? What do you hope to see in the Arrowverse crossover? Share your thoughts in the comments below.

Crisis on Infinite Earths will begin on Dec. 8 at 8/7c on The CW.