The CW's Arrowverse marked 2021 as a year with beginnings and endings as several fan-favorite series came to a close while others made their big debut or charted new directions within the shared television universe. From The Flash kicking off its eighth season with the "Armageddon" crossover event to Black Lightning and Supergirl taking their respective last bow, there were plenty of major moments that got audiences talking as DCTV clocked in another successful year of buzzworthy scenes and developments.

Here are the five biggest events to come to the Arrowverse across 2021 as the iconic DC heroes enjoyed new beginnings and epic finales as they continued to defend the shared television universe.

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Black Lightning Comes to an Electrifying Finish

jefferson pierce as black lightning

While the world of Black Lightning was incorporated into the main Arrowverse by "Crisis on Infinite Earths," the acclaimed series came to an end with its fourth season this past May. Black Lightning Season 4 kept the focus on Jefferson Pierce's family, as well as their longstanding feud with the nefarious supervillain Tobias Whale, with these major narrative threads coming to a head in the series finale.

Black Lightning paid off on all these developments, from Jefferson finally reconciling with his wife Lynn to his daughters following in their father's footsteps as their own superheroes. The finale's showdown was particularly memorable, with an emotional confrontation between Black Lightning and Tobias while setting up an intriguing direction for the potential spinoff for the antihero Painkiller that was ultimately canceled.

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The Reverse-Flash Launches His Ultimate Revenge

Apart from the occasional guest star, the Arrowverse has largely taken it easy recently in regards to the big, bombastic crossover events that culminated in "Crisis on Infinite Earths." This changed with The Flash kicking off Season 8 with a five-part crossover "Armageddon," with the extraterrestrial antagonist Despero hunting Barry Allen after accusing him of destroying the world in a prophesied future.

While the initial episodes of "Armageddon" were a bit uneven, the crossover event truly pulled out all the stops when the true culprit behind the earth-shattering plot was revealed to be the Reverse-Flash with his most dastardly revenge scheme yet. By the time the dust settled, the Arrowverse saw a new Atom while Barry received his iconic gold boots as he restored all of reality and cleared his name.

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A New Batwoman Comes to Gotham City

Batwoman Season 2 Ryan Wilder Banner

Batwoman is the returning Arrowverse series that saw the most upheaval in 2021, with original series star Ruby Rose departing the show between seasons. Taking up the cowl in her place is Javicia Leslie as new character Ryan Wilder, a superhero more in-line with the people of Gotham City than the billionaire Kate Kane. Despite initially lacking the resources Kate possessed, Ryan quickly proved herself more than worthy of the mantle of Batwoman as defended Gotham from a growing number of supervillains.

While Ryan's debut as Batwoman certainly started Season 2 with a splash, there were plenty of developments across the year to keep the Crimson Knight on her toes, from familiar foes resurfacing to menace Batwoman to an unexpected alliance with Alice. And Ryan definitely stands alone in her mission to protect Gotham, with Luke Fox embracing his own superhero destiny as the armored Batwing.

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Supergirl Closes on a Hopeful, Loving Note

supergirl alex and kelly's wedding

Supergirl has always been a show about seeking the truth, more specifically, seeking the truth in regards to love in all of its forms. This was made all the more evident by Supergirl's sixth and final season, with the first half of the season involving reunions between friends and family after Kara was stranded in the Phantom Zone while the second half saw Alex Danvers and Kelly Olsen build a family of their own.

This culminated in Supergirl's series finale that centered on Alex and Kelly's wedding while J'onn J'onzz and M'Gann prepare to take their romance to the next level. Amidst all the returning characters from seasons past, including a surprise reappearance by Cat Grant, the series concluded with its commitment to the truth as Kara publicly came clean about both sides of her identity to live a fuller life -- though some fans were vocally frustrated about where the finale left Kara's love life.

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Superman & Lois Takes Flight

One of the biggest series premieres of 2021 was Superman & Lois, putting Tyler Hoechlin and Elizabeth Tulloch's Clark Kent and Lois Lane center stage after their past guest appearances in the Arrowverse. The new series was praised for its cinematic-level quality, strong handle on the couple and their family and emotional themes throughout its inaugural season.

While there are plenty of memorable moments across Superman & Lois Season 1, the series premiere is one of the best episodes in the Arrowverse to date, from the introduction of its premise and main cast to flashbacks to Clark and Lois' first adventures together, including Hoechlin's Superman wearing a classic, Golden Age-inspired costume.

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