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A disturbance in the Soviet 2-year old dominion and completion of a Chrono Backpack creates an opportunity for the Allied forces and Siegfried to extract Special Agent Tanya from the Soviet prison in city-turned-fortress Warsaw with a new suit.
—Mission description

Operation: The Mermaid is the first Allied Act Two campaign mission.


Commander, it seems the time has finally come. Intel has reported multiple abnormal signals across the globe, with the strongest emanating from Moscow. It appears that the Soviet dominion in Europe has begun massive redeployment operations for some reason, and their communications are in chaos. This might be the chance we've been waiting for. As you probably know, not long after the defense of the SteinsTech University in Germany, Special Agent Tanya's chronoshift attempt has failed, which resulted in her capture and imprisonment at a previously unknown location. We have recently discovered that she is being held in the Soviet-converted fortress of Warsaw. The fortress itself is heavily guarded, as it contains the Soviets' military and political administration for Poland, which means cracking into it with conventional means is out of the question. Fortunately, we now have an ace ready to deploy.

Utilizing his newly developed prototype, the Chrono Backpack, Siegfried has volunteered to chronoshift himself into Warsaw. Once free, both Tanya and Siegfried must reach the extraction point on the right bank of the Vistula River in order to get them out of there. Avoid raising the alarms or engaging in unnecessary skirmishes as we cannot risk Tanya or Siegfried's safety during this operation. Reinforcements can't be deployed within the city, so evacuate them quickly before the Soviets realize something is amiss.

Objective 1: Get Tanya near a power source building.
Objective 2: Get Tanya into an Allied transport vehicle.
Objective 3: Don't get Tanya or Siegfried killed.


Freeing Tanya and finding a new power source

Siegfried finally arrives to free Tanya from captivity

As soon as Siegfried entered the holding area where Tanya was, two Conscripts tried to stop him. Siegfried turned the tables on the soldiers and phased them out of existence. After the soldiers were erased from history, he gave Tanya a new laser rifle. However, the Chronoshift that Siegfried used to get into the prison caused the rifle to discharge its energy, forcing the two to find a new power source.

Allied Intel suggested that there was a Soviet outpost containing Tesla Reactors near the Polish Sejm building. Should the two of them raid that outpost, they would be able to find a crate carrying a power source to recharge the laser rifle and some C4 explosives for Tanya. With few other options, the duo proceeded to the outpost, clearing any obstacles and hostiles in their way.

After fighting their way past a lot of patrols, Tanya and Siegfried made it to the Soviet outpost. Tanya moved in and grabbed a crate containing the much needed equipment. Now that Tanya was armed, she would be evacuated via Allied transport so they could chronoshift out of Warsaw.

Escaping from Warsaw

Just as Tanya and Siegfried began to move, the Soviets caught on to what they were doing and raised the alarm. Enemy reinforcements were sent rapidly to their location, with enemy Wolfhounds heading to Warsaw in minutes, forcing the two of them to make a dash for the river.

After fighting through another Soviet outpost, Tanya and Siegfried made it to the Warsaw Mermaid. The escape route to the transport was on the other side of the mermaid, but it was blocked by barricades. However, Tanya made short work of the barricades with her C4, while Siegfried covered her retreat, erasing enemies as they approached.

The escape was rough but Tanya and Siegfried made it to the Archon AMC transport. Tanya entered the vehicle and was chronoshifted out of Warsaw, while Siegfried used his chrono backpack to make the return trip back to the British Isles.


Tanya and Siegfried are now sound and safe in the London Fortress. Having confirmed the effectiveness of the new tech, Siegfried can resume his work on the Chrono Legion, which we'll use to deal devastating blows to our enemies.
—Battlefield report

Tanya and Siegfried had successfully managed to escape from Warsaw and are safely back in the United Kingdom. Having confirmation of the effectiveness of the new chrono tech, Siegfried resumed his work on the creation of a "Chrono Legion", a division of specially trained Allied soldiers armed with the new tech.

The Allied Nations now believed it was time to strike back at both the Soviets and this new threat that has just emerged from the shadows. They received word that Rome has fell to this new enemy and had begun work on a new Psychic Amplifier.

At this point, the Allies knew who they were facing. Yuri had betrayed his Soviet masters and had created an army to take over the entire planet.

The Allies prepared their diminished forces and begun their assault on Rome.

Difficulty changes


  • More barrels will be on the map.
  • The location of the specified evacuation point will be revealed on the minimap.
  • The player can find a firepower upgrade crate and a heal crate near the initial position, but the way leading to them will be blocked by Concrete Wall.
  • The amount of enemy patrol troops are the least in this difficulty.


  • The kennel on the map will continue spawn the Attack Dogs to chase the heroes before being destroyed by the player.


  • The amount of enemy patrol troops are the most numerous in this difficulty.
  • The kennel on the map will continue spawn the Attack Dogs more than on Normal difficulty to chase the heroes before being destroyed by the player.
  • A group of Pyros will attack the heroes when they approach the gate near the initial position.
  • There will be an additional Gyrocopter stationed on the player's path.

Easter egg

  • Let Siegfried kill all Pyros next to a castle, than an armor crate and firepower crate will appear.
  • Let Tanya find and attack a small car among limousines near the Sejm building, the car will chronoshift to different places many times. It will eventually stay at bottom right corner of map, destroy it will generate a map reveal crate.

Behind the scenes

  • This mission is named after the Mermaid of Warsaw statue that can be seen next to the river in the mission itself.
    • It was known as The Siren in early development because Speeder mistook the statue for a statue of a siren.


Great call, Commander. Did you really think elimination of this object would go unnoticed?
—Allied intel
  • The Ujazdów Mansion and Sejm buildings are featured in this mission. If either of them are destroyed, the Soviets will send Wolfhounds to hunt for Siegfried and Tanya earlier than intended.
  • This is the last Allied mission in which the Russians are the main antagonists, as almost all subsequent missions involve fighting the Epsilon instead.