The original Gears of War trilogy was a landmark achievement in 21st-century gaming. Not only was its gameplay groundbreaking, but it managed to establish a world as memorable and immersive as other 3rd-person shooter stalwarts of its generation like the Halo and Mass Effect series. Sprinkle in a healthy dose of supplemental transmedia over the years, and the Gears universe has taken on a life of its own--a far cry from the early criticisms of the first game claiming it lacked the world-building necessary to draw players into its story.

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Fast-forward to today, and the franchise is as strong as ever, following the story of the next generation of Delta squad in their ongoing struggle to survive on planet Sera. Before the Swarm War that's taking part in the recent chapters of the series, though, was the infamous Locust War that ravaged humanity for nearly two decades. For players too young to have played the original trilogy, there are several important threads connecting these two turbulent eras dating back to the years even preceding Emergence Day (E-Day).

Here is a refresher on ten of the most crucial things you didn't know happened in the Locust War. Spoilers abound!

10 Queen Myrrah Revealed Her E-Day Plan to Adam Fenix

Queen Myrrah Gears of War

In the decade before E-Day, the Locusts who were living in the Hollows below the Seran surface were locked in a brutal struggle with the Imulsion-infected scourge called the Lambent. Queen Myrrah, desperate for a solution, employed the human scientist Adam Fenix (father of main protagonist Marcus Fenix) to come up with a cure for the lambency.

She revealed to him a whole four years before E-Day, that should he fail, she planned to invade the surface at the cost of human lives in order to save the Locusts. As Gears history would have it, Fenix would fail to come up with a cure for lambency and her ambition would come to fruition.

9 Defeats at Halvo Bay and Ostri

Halvo Bay Battle Gears of War

The opening year of the Locust War was an abject disaster for the human nations of Sera. The Locust invasion at Halvo Bay was a pyrrhic victory for the humans, but the city and its military installations fell largely out of use. The long-term impact of this three-month-long battle was the eventual adaptation of the humans to the Locust's strategic battle prowess.

Similarly, the fall of the nation of Ostri demonstrated how the disunity leftover from previous human wars could lead to spectacular loss of lives and territory against a singularly minded enemy. The legacy of Ostri was the controversial decision by Chairman Richard Prescott to unleash the Hammer of Dawn countermeasure which ravaged the surface of Sera.

8 Sgt. Gabriel Diaz Was Saved by a Bank

Sgt. Diaz Hammerstrikes Gears of War

Gabrial Diaz, the main protagonist of the turned-based strategy game Gears Tactics, was sent on a mission to recover sensitive information from CIC Aldair a mere two hours before the apocalyptic Hammer strikes began. Luckily for him and Maj. Sid Redburn, an abandoned bank nearby had its vault left wide open, allowing them to take shelter from the city's destruction.

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If not for that serendipitous bunker, the strikes would have taken out Diaz, who was a crucial player in how the early years of the Locust War would shape out. His actions following the Hammer strikes would set the Locust onslaught back significantly.

7 The Assassination of Locust Scientist Ukkon

Ukkon Gears of War

Thanks to Sgt. Diaz, the mad scientist Ukkon was dispatched before he could accelerate the Locust offensive. Ukkon was responsible for creating the weaponized monstrosities out of creatures native to the Hollows below Sera such as Hydras, Reavers, and Brumaks.

But, that wasn't all he was doing; Ukkon was also using Imulsion to convert captured humans into Drones, or footsoldiers for the Locust army. Upon learning this truth, Maj. Redburn and Sgt. Diaz decided to keep it a secret, the latter choosing instead to dedicate the rest of his life to exterminating Ukkon's surviving creations as a rogue operative outside of COG control.

6 Locust General RAAM Captured Ilima City

General RAAM Battle Pose Gears of War

Fans of the series will be familiar with the human bastion city Jacinto built upon the Jacinto Plateau--the most defensible position during the Locust War due to the hard granite beneath its foundations.

Before Queen Myrrah could launch her full-scale invasion of the plateau, her revered general RAAM captured the strategically located Ilima using Nemacysts and Kryll to eradicate the population. Seeing the ravenous Kryll swarms devouring people en masse is almost enough to qualify it for one of the darkest moments in the series.

5 The Riftworm Awakened by The Lightmass Offensive

Riftworm Emerging Gears of War

The Lightmass Offensive was a watershed moment in the struggle against the Locusts. Kryll breeding grounds were eradicated and human forces around the Jacinto Plateau were given a moment to finally rest and recover.

Unfortunately, the destructive blast woke up the devastating beast known as the Riftworm, which the Locust army used to destroy several COG outposts and three human cities via subterranean assaults. As menacing as the beast was though, Delta Squad didn't even need a Hammer of Dawn to take it down in the end, just a lot of guts and a few good chainsaws.

4 The Locust Fail to Take Jacinto

Marcus Fenix at Jacinto Gears of War

Another unintended effect of the Lightmass Bombing was the necessitation of Queen Myrrah to end the war faster. The means she and the Locust chose to accelerate ultimate victory was an all-out siege of Jacinto City.

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COG forces successfully defended their position on the plateau, giving them the morale boost necessary to carry out the monumental Operation: Hollow Storm. This stretch of action is one of the most exhilarating in the whole Gears franchise--good enough to make loyal fans yearn for a much-needed Gears of Wars 2 remastering.

3 Flooding Jacinto Accelerated the Rise of the Lambent

Gears of War Lambent Locust Menacing

Thanks to a message from Adam Fenix found in Nexus during the COG underground invasion, Marcus Fenix and Delta Squad got the idea to sink the city of Jacinto to flood the whole subterranean Locust network.

Although they succeeded, the unintended consequence of doing so was to disperse the toxic Imulsion substance through fresh and ocean water, spreading the infectious blight to all lifeforms, Locust and human alike.

2 The Halvo Bay Blunder

Raven Over Azura Gears of War

With the struggle against the Lambent now in full swing for both COG and Locusts, the remnants of Queen Myrrah's forces kept a low profile. A vital opportunity for her and the crippled Locusts arose when a COG scout Raven returned to Halvo Bay to scour for resources.

As it turned out, the Locusts turned Halvo Bay into their new stronghold, which allowed Myrrah to tail the Raven all the way back to the hidden sanctuary of Azura. This costly mistake led to the infiltration of the secret city by the Locusts.

1 Crystallized Locusts Were Amassed in Burial Sites Across Sera After V-Day

Locust Pods Gears of War

In the end, ultimate victory was achieved by humans thanks to the brilliance and sacrifice of Adam Fenix who managed to eradicate both the Lambent and much of the Locusts with the Imulsion Countermeasure Weapon.

Vast amounts of Locust bodies became crystallized when the weapon activated and were presumed to be lifeless shells. The human government decided to dispose of them in mass graves around the planet as the recovery process of cities and the environment began. Unbeknownst to them, however, these crystallized corpses were merely in hibernation, lying dormant until the day they would emerge as the Swarm.

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