Axis heavy support for Zverograd

The horrific battles to seize Zverograd have turned into a meatgrinder where all three sides have fought themselves into an uneasy standstill. To help break the stalmate the axis forces have brought up several heavy artillery pieces able to hurl huge explosive rounds into the maelstrom from the safety of 15 miles behind the front lines. 

The guns are so big that they are moved to within 20 miles of their destination by rail and then unloaded and moved to their firing positions by modified heavy walkers. The walkers also provide air and ground protection once the gun is ready for firing. The walkers have much of their heavy armour removed so they can carry the huge load and are basically type 3 walkers in combat.