A water-walker (Wasser-wanderer in German) is a walker which can walk along the bottom of the ocean or a river at relatively shallow depths. To be taken across an ocean, it must be carried by boat.
In the seriesEdit
At a party at the Serbian consulate, Lilit tells Deryn that she needs to unofficially pass information to her. In a newsreel cinema, she tells Deryn that the ambassador has heard from the Germans about a water-walker that they plan to send against Mr. Tesla. Lilit tells Deryn because she believes that the Leviathan is capable of stopping the water-walker.
Deryn tells Dr. Barlow about the water-walker, but says that she cannot reveal the source. Dr. Barlow tells the Leviathan's bridge, and the crew decides to stay and wait to catch to walker on United States soil.
Deryn also tells Alek, and he asks Klopp about the water-walker. Klopp corrects Alek's impression that it is a U-boat with legs, and tells him about how water-walkers are used to cross lakes and rivers. Hoffman reminds him that a water-walker could be taken across an ocean on a boat.
On the night that the Goliath is to be tested against Berlin, the Leviathan spots a water-walker and two escorts. The escorts are bombed, but Lord Churchill has ordered the Leviathan to allow one of the walkers to be destroyed on land, where it can be seen by the Americans. Deryn sends a messenger eagle to Alek to warn him, and he tells Tesla about the German attack. Tesla reacts by planning to fire the Goliath to destroy Berlin.
Alek fears that the Leviathan is too close to Goliath, and will be set on fire if the machine is fired. Alek asks Tesla to shut down Goliath, but Tesla refuses, saying that no one will believe that Goliath works if it is destroyed now. After Alek kills Tesla and shuts down Goliath, the electricity stored in Goliath destroys the water-walker.
When the destroyed water-walker is seen by the Americans, they enter the war on the Darwinist side.