Previous:	Raid on Antibaar
Concurrent:	Battle of Rayingri Raid on Solcrum Peak 15 Containment Breach Battle of Armstrong Skirmish in Synthetic Insights Skirmishes in the Aleutsk valley Battle of Peak 15
Next:	Hijacking of the SSV Normandy
Battle of Virmire Part of the Eden Prime War
Cpt. Kirrahe gives a speech to his men prior to the second phase
Date:	2 July - 11 July 2183 CE (9 days)
Location:	In and around the Virmire Heretic Fortress / Virmire / Hoc / Sentry Omega
Outcome:	Decisive Alliance/Union victory Complete destruction of the Virmire Heretic Fortress Breeding and production facilities for SA's krogan army destroyed Genophage cure research destroyed. Dr. Quiath Droya killed True nature of Sovereign revealed Sovereign and Saren Arterius escape Geth heretics suffer heavy casualties Ashley M. Williams and most of the 3rd INFILREG are killed in action
Belligerents Systems Alliance Salarian Union Saren's Alliance Geth Heretics Commanders Marcus L. Shepard Ashley M. Williams † Raebant Kirrahe Osei Rentola Saren Arterius Sovereign Quiath Droya † Unit P717 † Strength Phase I: Union Navy 1 Galisus-class troop transport SUV Endeavour Dates Special Tasks Group 3rd Infiltration Regiment 1,000 STG troops Phase II: Special Tasks Group 3rd Infiltration Regiment 894 STG troops Normandy Squad 7 combatants 1 M35 Mako Systems Alliance Navy 1 Normandy-class stealth frigate SSV Normandy Geth Heretic Army 30,000 geth troops 5,000 geth recon drones 6,000 geth assault drones 16,000 geth troopers 1,000 geth destroyers 1,000 geth juggernauts 500 geth hoppers 300 geth primes 148 geth armatures 52 geth colossi Geth Heretic Navy Fleet of the Herald 320 ships 1 Sovereign-class Reaper Sovereign Heretic Reserve Fleet 79 ships Indoctrinated forces 300 tank-bred krogan Casualties Phase I: 1 troop transport destroyed 106 STG troops killed Phase II: 678 STG troops killed Ashley M. Williams Total obliteration of geth heretic ground forces All tank-bred krogan wiped out All remaining indoctrinated forces killed Fortress completely destroyed Dr. Quiath Droya killed

"You all know the mission, and what is at stake. I have come to trust each of you with my life, but I have also heard murmurs of discontent. I share your concerns. We are trained for espionage; we would be legends, but the records are sealed. Glory in battle is not our way. Think of our heroes; the Silent Step, who defeated a nation with a single shot. Or the Ever Alert, who kept armies at bay with hidden facts. These giants do not seem to give us solace here, but they are not all that we are. Before the network, there was the fleet. Before diplomacy, there were soldiers! Our influence stopped the rachni, but before that, we held the line! Our influence stopped the krogan, but before that, we held the line! Our influence will stop Saren; in the battle today, we will hold THE LINE!"

— Cpt. Raebant Kirrahe to the men of the 3rd Infiltration Regiment prior to commencement of the battle's second phase.

The Battle of Virmire, also known as the Virminian campaign and codenamed Operation Deadshot by the STG, was one of the largest engagements of the entire Eden Prime War, fought between the forces of the Salarian Union's STG (who would later be reinforced by the Normandy Squad) and Saren's Alliance on the planet Virmire. The planet was chosen as the primary headquarters and base of operations for Saren's Alliance before the Eden Prime War began, with a large Geth Heretic Fortress, which had been built as far back as 2162 CE, being utilized as a springboard for numerous military campaigns. Saren Arterius and Sovereign expanded upon the fortress, utilizing it as a refueling station for the geth heretic fleets, and building numerous RnD labs to create a tank-bred army of krogan, while also researching a cure for the genophage, in the hope of securing the allegiance of Tuchanka. When hostilities began, the Salarian Union sanctioned STG operations to locate geth bases, and when they believed they had tracked down one of them to Virmire, the SUV Endeavour Dates was dispatched with the 3rd Infiltration Regiment under Raebant Kirrahe to reconnoitre the facility, and report their findings back to Sur'Kesh.

However, intelligence failed to realize they had in fact found the SA's primary base. As a result, resistance was heavier than expected, and the Endeavour Dates was forced to crash land on the planet. Kirrahe's men established a camp at the base of the facility, utilizing their presence to gather tactical and strategic information on the fortress' defenses. A distress call was dispatched, but when received by the Citadel Council, it was misinterpreted and only the Normandy Squad sent to assist in what they believed to be a reconnaissance mission. Upon arrival, both Kirrahe's and Shepard's men began working on a plan to neutralize the facility in an effort to deal a crippling blow to Saren's Alliance. A nuclear IED was built from the remains of the drive core of the Endeavour Dates, which was to be delivered to the center of the fortress and detonated.

The assault commenced the next day, with the 3rd INFILREG launching a diversionary assault on the front of the fortress, while the Normandy Squad snuck in from behind to neutralize the base's anti-aircraft screen. The assault proceeded as planned, and the bomb was delivered, only for Kirrahe's men to be pinned down. The result was Ashley Williams and Kirrahe's men being pinned by geth troops, forcing Shepard to save the latter. A brief encounter with Saren himself resulted in Saren's complete withdrawal, with Shepard and the survivors of the 3rd INFILREG escaping just before the bomb detonated, wiping out the entire fortress in nuclear fire. The battle was a decisive victory for Council forces, and the first documented event in which both Union and Alliance military forces operated together. However, it had one unintended side effect: Virmire was mistaken as the end of the threat Saren posed to the Citadel Council, which inadvertently led to a series of events that would culminate in the Battle of the Citadel.

The Battle of Virmire has a long-standing legacy. The 3rd INFILREG would be assigned numerous honors for their bravery and valor in the battle, and Kirrahe would be promoted for his actions. Gunnery Chief Ashley Williams' sacrifice would lead to her posthumous promotion to Lieutenant Commander: the rank believed to be equal of that which she would have had if she had not been blacklisted. The capital city of Virmire, Williams, is also named after her, and is located on the same spot where the fortress once stood.