The following contains spoilers for God of War Ragnarök, available now on PlayStation 4 and PlayStation 5.

One of the most challenging choices that developers of long-running video game franchises with consistent main playable protagonists have to make is deciding how the character will develop throughout the series. While less narrative-focused franchises like the Mario series can get away with having their protagonists undergo little to no character development, the protagonists of more story-driven game series must be changed by their experiences if the stories of each game and the greater narrative of the franchise are to have any weight.

When Santa Monica Studios announced their plans to reboot their critically-acclaimed God of War series with the 2018 game of the same name, the title's creative team made it clear that they planned to undertake the monumental challenge of developing the franchise's main protagonist Kratos into a more three-dimensional character. Against all odds, the team transformed one of gaming's most prolific killers into a relatable and even admirable figure in a way that doesn't betray pre-established elements of Kratos' character, creating what might be the most satisfying character arc in gaming history.

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The Early God of War Games Showcased Kratos' Slow Descent Into Murderous Rage

Kratos covered in blood in the original God of War

When players were formally introduced to Kratos in 2005's God of War, they were given a reasonably clear portrait of the man the Ghost of Sparta would be throughout most of the franchise. Having been tricked into murdering his wife Lysandra and his daughter Calliope by the Grecian god of war Ares, the former Captain of the armies of Sparta was willing to do anything it took to claim revenge on his former patron. He mercilessly cut down both dedicated servants of Ares and anyone unlucky enough to find themselves standing between him and his vengeance.

While the original God of War established the aloof and vengeful persona that Kratos would maintain through most of the series' Greek era, the games that succeeded it would begin to slowly expand on the Ghost of Sparta's character by offering more details about his traumatic past. Throughout the God of War: Chains of Olympus and God of War: Ascension prequels set before the original game, Kratos is depicted as a man more than capable of mercy, showing surprising restraint in the pursuit of his goals and even expressing respect and gratitude to the mortals and gods who helped him on his journey, while reserving his fury for his foes.

Unfortunately, despite Kratos' attempts to maintain his honor after his ascension to godhood, his resentment of the casual cruelty of the gods of Olympus and the lingering guilt he felt for murdering his loved ones gradually drove the Ghost of Sparta to embrace his darkest impulses. This growing frustration with his divine peers eventually hit a boiling point in God of War: Ghost of Sparta when Kratos discovered that his mother Callisto and his brother Deimos had been imprisoned and tortured by the Olympians for decades to prevent a prophecy that heralded their demise. Having learned that everyone he loved had been taken from him by the gods, Kratos swore revenge upon Olympus.

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The Later God of War Games Forced the Ghost of Sparta to Confront His Sins

Kratos in God of War III tearing Helios' head off

By God of War II, Kratos had given into his rage, leading the Spartans into war against the city of Rhodes for no other reason than to sate his bloodlust. After being betrayed and murdered by Zeus, Kratos embarked on a mad crusade to murder the King of Olympus, showing none of the mercy he'd shown in his earlier quests. Driven only by his desire for vengeance, Kratos became even more ruthless than he was in the first game, slaughtering monsters and mortals to reach the Sisters of Fate and undo his death at Zeus' hands. Even after learning from Athena that killing Zeus would bring the world to ruin, Kratos still attempted to claim his revenge and declared war on all of Olympus after Zeus escaped.

During God of War III, Kratos proved that there were no longer any limits to the lengths he was willing to go to claim his vengeance. Utterly consumed by rage, Kratos slew Olympian after Olympian, causing cataclysmic disasters to ravage Greece and bring a violent end to thousands of lives. However, Kratos' ascent of Olympus also showed that there was still a fair amount of humanity within the Ghost of Sparta through the affection he developed for Hephaestus' daughter Pandora, who bore a striking resemblance to Kratos' daughter and wasn't afraid to criticize him for the destruction he caused in his pursuit of revenge.

By the final hours of God of War III, Kratos had finally come to understand that claiming vengeance against the gods wouldn't relieve him of the guilt he felt for killing his family and that his quest for revenge had brought Greece to the brink of ruin. Fortunately, a near-death experience during his final battle with Zeus gave Kratos a chance to reunite with the spirits of his family, who encouraged him to let go of his guilt. While Kratos still killed Zeus, he did so to end his tyrannical rule and give the people of Greece a chance to rebuild their lives free from the cruelty of Olympus.

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The Norse Era Shows How Kratos' Experiences Changed Him for the Better

God of War Ragnarok Faye and Kratos

Although Kratos' arrival in Midgard hasn't been explored, it's clear that he had become a different person by the time his son Atreus was born. Having witnessed firsthand the cost of pursuing revenge above all else, Kratos renounced the rage that once defined him and went out of his way to teach Atreus the dangers of holding grudges and acting out of anger. Even when the pair find themselves under direct assault from Odin and Thor throughout God of War Ragnarök, Kratos only acts in defense of himself and his allies, even reacting to the death of his close friend Brok by allowing himself to grieve rather than give into anger.

Given the sheer magnitude of Kratos' body count, the task of developing him into a more emotionally-open character seemed all but impossible to many long-time fans of the series. However, the writers of 2018's God of War managed to make this transition feel incredibly natural by acknowledging what Kratos has done and how his actions affected him. Rather than downplay or ignore Kratos' past actions to avoid confusing new fans or streamline his development, God of War and God of War Ragnarök openly address the events of past games to show how each act of betrayal and violence changed Kratos into the man he is now.

In an age where video game developers regularly push the boundaries of how stories can be told in games, Santa Monica Studios' willingness to radically change one of gaming's most recognizable characters was a bold step forward. By taking advantage of the subtle character development that Kratos had already gone through in past games, the developers of the two newest titles managed to make his growth as a character feel organic and natural. While the ending of God of War Ragnarök leaves the future of the series uncertain, the quality of Kratos' character development isn't.