Even the most legendary fictional heroes couldn't have succeeded without help from allies and friends. It's usually up to the protagonist to challenge the villain, find the sacred item, or make the ultimate sacrifice in the end. But without support from those around them, they likely would have failed long before the story's climax.

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Some stories — specifically from popular video game titles — include a wide cast of characters, often partnering up the heroes with invaluable allies. There have been many iconic and beloved character duos throughout video game history that prove even heroes need support and companionship. Several duos define the individual characters themselves, and any attempts to separate them would change the overall story entirely.

10 Ellie And Joel Developed A Father-Daughter Dynamic

The Last of Us

The Last Of Us: Ellie looks out the window while Joel drives

The father-daughter relationship between Ellie and Joel took time and effort to develop over the course of The Last of Us Part I. It was clear from the beginning that the two characters needed each other, but the losses they both suffered drove a wedge between them. It took a journey across America to bring them together and heal their past traumas.

Ellie, orphaned and burdened with an immunity to the zombie virus, knew she couldn't find her way to safety alone. Joel, unintentionally tasked with protecting her, struggled to acknowledge his growing protectiveness. It was only after they'd both saved each other that the two of them fully embraced their father-daughter dynamic.

9 Sans And Papyrus Are Undertale's Iconic Skeleton Brothers

Undertale

Sans and Papyrus from Undertale

Of the dynamic and unique cast of characters from Undertale, none are more popular and recognizable than Sans and Papyrus, the skeleton brothers. With names based on their in-game dialogue fonts, the two brothers are the first characters encountered after leaving the ruins. Their banter and quips are hilarious, and their opposite personalities fit well together.

Both Sans and Papyrus have very distinct characteristics. Sans is the lazy, pun-loving older brother, while Papyrus is the energetic and naive younger sibling. They are certainly unique characters, but together they provide some of the best moments from Undertale's entire story, including the game's most difficult and heartbreaking encounters.

The Legend of Zelda

Zelda and Link side by side from Legend of Zelda Ocarina of Time

Zelda and Link's friendship transcends centuries, persisting across several reincarnations throughout Hyrule's history. Each game from The Legend of Zelda franchise includes alternate versions of the iconic duo, as well as the villain Ganon, locked in their eternal battle for good and evil.

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Without her champion Link, Zelda could not fulfill her prophecies and properly wield the Triforce of Wisdom. Link wouldn't stand a chance against Ganon's dark forces alone. But together, along with the Triforce and Master Sword, Link and Zelda make a powerful and iconic duo.

7 Sonic And Tails Have Been Friends Across The Entire Franchise

Sonic the Hedgehog

Sega's iconic mascot Sonic, from the Sonic the Hedgehog franchise, might be its most famous character, but Sonic owes much of his success to his friend Tails the Fox. First debuting in Sonic the Hedgehog 2, Tails has become one of Sonic's most trusted and valuable allies over the course of several games, tv shows, and movies.

Sonic has made several iconic friends across the franchise — like Knuckles, Shadow, and Amy — but Tails has been around longer than any other. Knuckles and Shadow are antagonists in several games and plots, and Amy isn't usually involved in the main story. Tails, on the other hand, has not only always been Sonic's ally but is a playable character in many games as well.

6 Geralt And Yennefer Are Powerful Allies And Dedicated Partners

Witcher

Geralt of Rivia, from the Witcher franchise, might advertise himself as a loner, but the truth is that he has many friends and allies who help him succeed. Yennefer of Vengerberg is arguably his most important partner, both romantically and platonically. The two encountered several physical and emotional obstacles in their relationship, yet they still found themselves drawn to each other.

Geralt is a ruthless and capable Witcher, but his muted emotions make it difficult for him to process moral issues. Yennefer, on the other hand, is passionate and bold. Their differences complement one another well both on the battlefield and in their personal relationship.

5 Mario And Luigi Are Nintendo's Iconic Plumber Brothers

Super Mario Bros.

Mario and Luigi pose together in Super Mario Bros

Not only are Mario and Luigi some of the most famous video game characters to date, but their companionship has persisted across several decades of the Super Mario Bros. franchise. Mario may be Nintendo's mascot, but his younger brother Luigi is always right alongside him. In some cases, like in Luigi's Mansion, Luigi himself becomes the temporary protagonist.

In nearly every Mario game since the original arcade cabinets, Luigi has been either a playable or supporting character. In contrast to Mario's happier and more optimistic attitude, Luigi is more fearful and shy. Together they make an iconic and memorable duo, recognizable even outside the gaming community.

4 Sully Has Always Been Like A Father To Nathan Drake

Uncharted

Nathan Drake hands Sully Sir Francis Drake's journal in Uncharted Drakes Fortune

Nathan Drake, the adventurous treasure-hunter, and Victor "Sully" Sullivan, the more level-headed strategist, have been partners since the first Uncharted game. In every grand adventure and quest that Nate pursued, Sully was always right beside him, offering advice and keeping him alive. The pair's banter and sarcasm became an iconic staple of Uncharted's sharp writing.

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While the two don't always see eye to eye, Nate and Sully are completely loyal to each other. Nate's impulsiveness was always kept in check by Sully's caution, but without Nate's ambition, Sully would likely have never become such a successful treasure hunter. Together, they make a hilarious and iconic duo.

3 Sora And Riku Protect And Inspire Each Other

Kingdom Hearts

Sora and Riku Fighting Final Form Xemnas

There are plenty of iconic characters throughout the Kingdom Hearts franchise, including characters from Disney and the Final Fantasy games, but the series' most important pair are Sora and Riku. Both have been friends since the franchise's first game, and have overcome several struggles and arguments over the course of the series' complex story.

Sora, the Kingdom Hearts series' main protagonist, is famously naive and impulsive. He has good intentions but often handles conflict in childish ways. Riku, on the other hand, has both wielded and overcome the darkness itself and pledged to use his powers to protect Sora and his friends. Riku is constantly defending Sora and Sora is constantly inspiring Riku. Neither would have gotten far in the series without the other.

2 Master Chief And Cortana Are Loyal Allies And Friends

Halo

Master Chief and Cortana reunited in Halo

Halo's iconic mascot, Master Chief, is never far from his AI companion Cortana. Even Chief's superhuman feats and enhanced abilities would amount to nothing without the guidance and sharp wit of Cortana, who has protected and assisted Chief countless times over the course of the Halo series. Since the franchise's first game, Halo: Combat Evolved, the two have been inseparable partners.

Without Cortana's knowledge of the Covenant and the Halo rings, Master Chief and the humans would likely have failed to protect the universe long ago. Chief's bravery and loyalty, combined with Cortana's quick thinking and guidance, created a powerful and iconic duo.

1 Playing With Both Cuphead And Mugman Makes The Game Significantly Easier

Cuphead: Don't Deal With the Devil

cuphead mugman king dice the devil

Cuphead and Mugman, originally from the Cuphead: Don't Deal With the Devil video game, are another iconic pair of brothers. Not only do their personalities complement each other, but the gameplay itself is significantly easier when played with two players. Both Cuphead and Mugman are playable characters, and fighting bosses with both brothers gives players a powerful advantage.

Cuphead is the more impulsive of the two brothers, while Mugman is more observant and cautious. It's Cuphead's fault that the two brothers lost their souls to the devil, but Mugman sticks by his brother's side nonetheless. Their combined powers make the boss fights significantly easier, allowing one brother to revive the other mid-fight if their health drops to zero.

NEXT: 10 Best Video Game Side Characters Who Always Save The Day