The Resident Evil series has been running strong for 25 years, with March 22 celebrating the quarter-century anniversary of the release of the first game in the series. Throughout this time, the franchise has spawned countless clones, numerous spin-offs, and an entire creative universe that expands beyond the realm of video games.

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Capcom has proven that anything can become canon in the series and that all the games are important. Perhaps the greatest examples of this are The Chronicles games released for the Nintendo Wii and the PlayStation 3. The events of these games fill plotholes left by the other games and answer some very important questions. Yet, only fans who played these games will know the full extent of their importance to the story of Resident Evil.

10 How Wesker Escaped The Arklay Mansion

Resident Evil Umbrella Chronicles Wesker Official Art

Many fans were excited to be placed in the shoes of the series villain Albert Wesker in Resident Evil: The Umbrella Chronicles. After completing the game's second main scenario that covers the events of the original Resident Evil's "Mansion Incident," players unlock new chapters where they play as Wesker.

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In the chapters titled "Rebirth," players discover how Wesker escaped the Arklay Laboratory with his newly gained powers from the T-virus. Wesker was forced to beat the self-destruct set by the S.T.A.R.S team as he fled through hordes of monsters to escape the Mansion. This event would be one of the catalysts to his long reign as the top villain in the series.

9 The Fate Of Lisa Trevor

Resident Evil Lisa Trevor Standing In a Doorway

Lisa Trevor stands as one of the most depressing and terrifying monsters in the entire franchise. Her family was kidnapped by Umbrella and experimented on for years. Lisa became a lab rat that was injected with countless drugs and viruses, transforming her into the horrific monster players faced in the Arklay Mansion.

In Resident Evil (2002), players defeated Lisa in the tomb of her mother, located underneath the mansion's foundations. This was assumed to be the canon death of the seemingly invincible monster, but Resident Evil: The Umbrella Chronicles showed that Lisa survived her fight in the tomb. She comes back to harass Albert Wesker as he attempts to escape the mansion, but she is defeated after Wesker drops a chandelier on top of her. Pinned under the weight of the chandelier, Lisa Trevor presumably dies in the destruction of the mansion.

8 The Relationship Between Chris And Forest

Resident Evil 1 Remake Chris and Forest

Forest Speyer was a member of the S.T.A.R.S Bravo Team originally sent to the Arklay Mountains to investigate the string of cannibal murders in the area. He split up with his team to make a complete sweep of the Arklay Mansion but was killed by crows infected with the t-virus on the east terrace.

In Resident Evil, players encounter Forest as a zombie. Umbrella Chronicles reveals the backstory between Chris Redfield and Forest when they fight on the east terrace. After putting Forest down, Chris regretfully says that he'll miss their target practice sessions. Chris and Forest were the best marksmen in the unit and had a close friendship. In the end, Chris had to shoot his own friend.

7 The Truth Of Umbrella's Collapse

Resident Evil 4 Intro Monologue Screenshot

In the beginning monologue of Resident Evil 4, players listen to Leon Kennedy as he explains how Umbrella's secret research went public and their stocks crashed, leading to the end of the company. Though the business collapse was the main story given to the public, Umbrella's fall was much darker and violent than just a stock crash.

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Umbrella Chronicles reveals how there was actually an entire military campaign against Umbrella, led by Chris Redfield and Jill Valentine. The duo led an armed assault against Umbrella's most important facility located in the Russian mountains. They were intent on finishing Umbrella for good by destroying the Red Queen data center and handing the evidence of Umbrella's sins to the general public.

6 Umbrella's Development Of T-A.L.O.S

Resident Evil Umbrella Chronicles TALOS Fight Screencap

Fans of the series have fought many a Tyrant, beginning with the final boss of Resident Evil. Tyrants are superhuman monsters made from the T-virus (Tyrant Virus). They are an iconic enemy in the series, producing creatures such as Nemesis and Mr. X. The final chapter of the main story in the Umbrella Chronicles shows off Umbrella's vision for the ultimate bioweapon known as T-A.L.O.S (Tyrant-Armored Lethal Organic System).

This colossal monster is a super-enhanced Tyrant with powered armor and heavy weaponry, all being controlled by a computer system. This monster was originally housed in the Arklay Laboratory but was moved to the Russian HQ by Oswell E. Spencer. Luckily, Jill and Chris caught up with it and destroyed it before any more could be made.

5 Wesker's Involvement In Umbrella's Downfall

Resident Evil Umbrella Chronicles Wesker Aiming A Silenced Handgun

Though originally employed and raised by Umbrella, Albert Wesker was a key part of the company's downfall. Long before he kills Oswell E. Spencer in Resident Evil 5, Wesker was involved with the destruction of Umbrella alongside his old subordinates Chris and Jill. Wesker was at the Russian Umbrella HQ while Jill and Chris' full assault was taking place.

Wesker had no interest in anything like saving lives or destroying bioweapons though. He intended to steal Umbrella's entire data cache for himself, which he was ultimately successful with. After defeating two modified Tyrants, Wesker faced one of the last leaders of the company, Sergei Vladimir. Vladimir mutated into an agile bioweapon, but Wesker easily disposed of him and completed his mission. He stole Umbrella's data and shut down the Red Queen, ultimately destroying Umbrella in the process.

4 How Ada Really Escaped Raccoon City

Resident Evil Umbrella Chronicles Ada Wong Standing Outside the Apple Inn

Ada Wong remains one of the more mysterious characters in the series. Her true intentions are never known, and she's nearly always skirting the lines between hero and villain. In the events of Resident Evil 2, Ada posed as an investigator to Leon Kennedy and used him to aid her own goal of obtaining a sample of the G-Virus. She was eventually severely injured and Leon thought she had died.

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However, in true Ada fashion, she was simply playing an act. After giving Leon a rocket launcher to defeat the Super Tyrant, Ada's actions were revealed in Resident Evil: The Umbrella Chronicles. She had to move through a monster-infested Raccoon City and contact none other than Albert Wesker to reveal that she had a sample of William Birkin's skin and thus a sample of the G-Virus. She is barely rescued by her contacts at Umbrella and narrowly escapes Raccoon City before it is bombed.

3 Leon's Past With Jack Krauser

Resident Evil Darkside Chronicles Jack Krauser Looking Forward

During the final acts of Resident Evil 4, players confront Jack Krauser. At the time, he hadn't appeared in any other games in the series yet there was history between Leon and himself. Players were left wondering what Krauser had done before and how he knew Leon before the events of Resident Evil 4Resident Evil: The Darkside Chronicles revealed that Krauser helped Leon during Operation Javier.

The two were tasked with investigating an outbreak in South America and destroying the viruses and bioweapons present. Krauser was an elite soldier from the US SOCOM unit. Though he was much more experienced than his young partner, it was Leon who had been assigned the task thanks to his special government training and experience during the Raccoon City outbreak. Krauser was simply there for support, and this planted the seeds of jealousy within him.

2 How Leon Became A Master With Knives

Resident Evil 4 Leon Knife Fighting Jack Krauser

As Jack Krauser was trained by the US special forces, he is a master of close-quarters combat, especially with knives. He brings this wealth of knowledge with him to Operation Javier where he works with Leon Kennedy to suppress an outbreak in South America. Krauser is intensely interested in Leon's experiences in Raccoon City and learns about how to combat BOWs from the young agent.

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In Resident Evil 4, it is heavily implied that Krauser taught Leon strategies and techniques for knife fighting. Interestingly, Krauser is extremely weak to knife attacks in his boss fight. Leon mentions knives throughout the game, telling Ada Wong that they are better for close quarters and eventually defeating Krauser in a knife fight. It seems that it was Krauser himself that taught Leon how to be a master with blades during the events of Operation Javier and the time before it.

1 How And Why Jack Krauser Became A Villain

Resident Evil Darkside Chronicles Krauser Stabbing A Snake in the Jungle

During the events of Operation Javier shown in Resident Evil: The Darkside Chronicles, players see Krauser working with Leon to end bioterror. This is a much different image of the character than fans remember from Resident Evil 4 where Krauser was a mutated human intent on killing Leon.

Krauser's mind and intentions become darker throughout the entirety of Operation Javier. He is jealous of Leon's recognition and reluctant to destroy the virus creating bioweapons in the area as he sees it as a path to greater power. Krauser's fascination with viruses becomes a desperate need after his arm is cut off during Operation Javier. He feels useless as a soldier and seeks Albert Wesker's help in becoming powerful once more.

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