Arrowverse Crossovers, Ranked

TVLine ranks the Arrowverse's biggest crossovers, from least to most "super."

1. "Crisis on Earth-X"

Supergirl 3x08/Arrow 6x08/The Flash 4x08/Legends of Tomorrow 3x08

Despite spanning four different shows and two different Earths, the hugely ambitious crossover is the most cohesive one to date, seamlessly flowing from one hour to the next. It also packed a punch, delivering emotionally resonant storylines about love and loss (R.I.P., Martin Stein) amid the fight against evil Nazi doppelgängers.

In addition to the much anticipated nuptials of both Barry and Iris and tagalongs Oliver and Felicity, viewers were treated to a Sara Lance/Alex Danvers hookup, the introduction of The Ray and his boyfriend Leo Snart (who would temporarily join Legends of Tomorrow) and a cameo from Colin Donnell (as Earth-X's evil Tommy). All that, and a certain, XS-ively chipper cater-waitress made her first appearance in a tease that would play significantly into The Flash's future. (But points off for no one RSVP'ing to Barry and Iris' wedding in a timely manner, ugh!)

5. "Duet"

Supergirl 2x16/The Flash 3x17

Stars Grant Gustin and Melissa Benoist have an undeniably winsome chemistry as superhero pals, and seeing them (and the rest of the ensemble) break out into song in the musical crossover is a treat. (Bonus points for that lovely Jesse L. Martin/Victor Garber/John Barrowman "More I Cannot Wish You" number.) But once you strip away the "Oh, my God, everyone's singing and dancing!" factor, the Music Meister's nonsensical agenda – he did all this, including attacking Central City, to teach Kara and Barry a lesson about... love? – exposes the threadbare plot.

6. "Elseworlds"

The Flash 5x09/Arrow 7x09/Supergirl 4x09

The Arrowverse bit off a little more than it could chew with this one. Whereas most of the crossovers can be summed up in one line ("Evil Nazis from another Earth invade!" "The Green Arrow and The Flash face off!"), "Elseworlds" contained about three concepts too many. There was the fun of Barry and Oliver swapping places. There was also the battiness of evil "Superman" and all the good guys turning bad in the third hour. Oh, and then there was the tee-up to this year's "Crisis on Infinite Earths" mega crossover. And shoehorned into all that was a mini-backdoor pilot for Batwoman. It's no wonder the much-missed Legends sat this one out; there was plenty going on already. Frankly, we would have been good with just the comedy gold of the body swap plotline.

3. "Flash vs. Arrow"/"The Brave and the Bold"

The Flash 1x08/Arrow 3x08

Considering this was the franchise's first big crossover, it's impressive just how self-assured and well-executed it was, even if it did very much feel like two separate episodes. Among the running jokes and continuing plotlines that were launched with this first foray: Iris' thirst for Oliver Queen; Dig's wonderment at Barry's speed; Oliver shooting Barry with arrows; the archer telling his speedster pal that guys like them don't get the girl; Dig and Lyla getting engaged; and Oliver running into his ex Samantha, whom we, the viewers, learned has a son. No wonder this first try spawned an annual tradition!

2. "Invasion!"

The Flash 3x08/Arrow 5x08/Legends of Tomorrow 2x07

There's plenty of reasons why the heroes vs. aliens matchup could have failed, but instead, the venture into really sci-fi territory worked. Facing genuinely creepy-looking ETs, Barry brought in an alien of his own for the good guys: Supergirl, whose intro to the full-on Arrowverse fold was, well, super. And while sandwiching Arrow's 100th episode into the middle of the extraterrestrial fight seemed like an ill-advised move, the "What if?" hour actually served as a touching tribute to the show's legacy.

8. "Legends of Today"/"Legends of Yesterday"

The Flash 2x08/Arrow 4x08

Remember the Hawk people? Yeah, we pretty much blocked them out of our memories, too. The two-parter was all about protecting them and setting up the forthcoming spinoff Legends of Tomorrow, to the detriment of both Flash and Arrow. From the clunky ancient Egypt flashbacks to the mustache-twirling villainy of Vandal Savage, this crossover missed the mark. And don't even get us started on the manufactured drama that was Oliver discovering he has a son and then agreeing to Samantha's demand that he not tell anyone, including his girlfriend Felicity, about the boy.

7. "Worlds Finest"

Supergirl 1x18

There's nothing wrong with Barry Allen's visit to the then-CBS drama per se, except that Supergirl's first taste of the Arrowverse was just that: a small sampling rather than a full-on crossover meal. And you can't blame us for wishing Kara and Barry's endearing new friendship had been the focus of the entire episode, especially when it gave us scenes like Kara's delightful reaction to the speedster racing out to grab her an ice cream cone.

4. "Crisis on Infinite Earths"

Supergirl 5x09/Batwoman 1x09/The Flash 6x09/Arrow 8x08/Legends of Tomorrow 5x01

There's no denying that the five-part, six-show event was epic. From the cameos (Ezra Miller! Smallville's Clark and Lois!) to Brandon Routh donning Superman's suit, once again, to the introduction of Black Lightning into the Arrowverse, this crossover checked off more fan wishes than Santa Claus on Christmas. But the giant scope and multitude of exposition required to tell the story of the entire universe's destruction also meant pivotal emotional beats like Oliver's death(s) often didn't get room to breathe, while key plot points came off as confusing. So while we applaud the ambition, skill and effort it took to pull off this "Crisis," let's not forget that sometimes less is more.