- "If we don't stop these things, everyone within a thousand miles dies."
- —Former Lt. James Dominic "JD" Fenix
The Mission to the Tollen Dam was an event that took place at the start of the Swarm War, four hours after the existence of the Swarm was discovered by a team of Outsiders led by former Sergeant Marcus Fenix. The mission's main objective was rescuing Reyna Diaz, the leader of an Outsider village attacked by the Swarm hours earlier. The fighting took place at the Tollen Dam, an old, pre-Imulsion era COG power plant that was a strategic importance during the Locust War. A side-effect of the mission was the restoration of the power to the dam and the surrounding cities that lost the power when the dam originally fell.
Order of BattleEdit
On the way to the DamEdit
At 03:46, after rescuing Marcus, learning the truth behind the Locust crystallization and successfully escaping from the osmium mine located beneath Fort Reval, Marcus suggested a detour in order to get backup, but was opposed by Kait. JD and the rest decided to head to the Tollen Dam, a pre-Imulsion era power plant, believing that Kait's mother, Reyna was taken to another Locust burial site which was located in the dam's drained reservoir. On their way, they stumbled upon the body of a Gear killed during the Locust War and took his COG Tag, hoping to take it to New Ephyra later. Del mentioned that the COG's data concerning the burial sites was classified and Marcus said that there could be hundreds of them scattered all over Sera.
As a Windflare hit their position, the squad battled their way to the dam. When the four managed to avoid the hazardous weather, Marcus and JD mentioned the COG's theories on the appearance of the Windflares such as holes in the planetary crust, sunspots and atmospheric distortion. At the base of the dam, Marcus said that he had already been here with the COG and soon after, they encountered a small group of Drones and a large creature that they dubbed "Carrier" after Del compared it's size to an aircraft carrier. As JD and his father and friends entered the dam, Marcus started remembering his and Delta-One's failed attempt at rescuing the Gears that are trapped inside the dam during the war when the Locust besieged the last power plant supplying the COG industry in the region.
Inside the Power PlantEdit
After entering the dam, the group discovered an elevator that would not work as there was no power. At Kait's suggestion, the group activated the last intact turbine and freed it of the Swarm tendrils. Though the wind moved the turbine in place of the long dried-up reservoir, the power was not restored as the surge was too much for the old circuits. After the group resetted the generators, the power was restored to the Tollen Dam, but the elevator was blocked by the Swarm pods from traveling to the top of the dam. Marcus admitted that the COG did a good job training JD and Del and was impressed by Kait's combat abilities. Kait said that she was trained by her mother and uncle, Oscar, an ex-Gear and veteran of the Locust War who was taken by the Swarm with the rest of the villagers. Hearing that, Marcus told Kait that he was sorry for her loss. They entered the elevator, but before it could reach the top of the dam, a cluster of pods located in the elevator's shaft blocked it, forcing the team to continue on foot through the Swarm-infested power plant. As another Windflare hitted the dam, they reached the top where they could see the dam's very advanced-looking Swarm hive. Kait urged the squad to get down there immediately and save her mother, but the rest managed to convince her that this was not only about her mother now and they would surely meet their demise if they entered it without any support. Marcus said that back at the Stroud Estate, he informed his "old friend" that he might need him later, but he would not be able to call him from the dam. Del pointed at a satellite dish located a few miles away with Marcus agreeing that it may work. As they fought the Swarm reinforcements and struggled with the wind, they found themselves under heavy fire from an MG nest located in a downed King Raven. JD quickly dealt with it by using a dead Siegebeast and created a bridge that the squad used to get through a hole in the dam.
Safe from the wind, JD, Del, Kait and Marcus continued their way through a substation to an exit, but discovered that the substation had no power. Reaching a control room, JD rerouted the main feed, restoring the power to the substation and from there, Fort Reval, Speyer, Bronn, Montevado, Ilima and Tollen and when they reached the transformer room, they encountered a Scion that looked familiar to Kait. She noticed that he was missing a hand and after remembering Reyna cutting one of her abductor's hands off, she realized that it was the same Scion that took her. Kait demanded the information on her mother and the place that she was being kept in which he responded by laughing and saying that "She was where she belonged". Then, the Speaker summoned his Swarmak mount, a Brumak crystallized after the Imulsion Countermeasure Weapon was deployed and attacked the four. JD and the rest managed to defeat him and his forces, leaving only the Speaker alive. He desperately tried to grab a Boomshot lying on the floor next to him, but was quickly incapacitated by JD and Del. Kait, assuming that all creatures from the dam's hive would hear her message through the Speaker declared that they are going to rescue her mother and burn the hive to the ground. Finally, Kait killed the Speaker by curb-stomping him and proceeded to Speyer with the rest of the team.