Aquatic Terrain Armored Transport

The Aquatic Terrain Armored Transport, also known as the AT-AT swimmer, was a war vehicle used by the Galactic Empire, designed to be the aquatic equivalent of the land-based AT-AT walker. They were piloted by specially trained Imperial Army pilots.

Characteristics
The AT-AT swimmer was manufactured in a joint venture between Kuat Drive Yards and Hydrospeare Corporation.

The command deck was attached to a broad area of the ship which contained passengers. It operated in deep sea operations alongside TIE fighter boats and aquatic assault stormtroopers and could be found in Imperial aquatic military bases. The AT-AT swimmer could also be deployed by the Y-85 Titan dropship. It could carry 40 troops, and its cargo capacity was 600 kilograms.

Its shell-like armor was designed to withstand and protect the vehicle from the crushing pressures of deep water, the effects of salt and water, and blaster fire. Its head was capable of providing firing arcs in all directions.

The AT-AT swimmer had two modified heavy laser cannons, much like its land counterpart. Its main body was broader than that of the AT-AT to accommodate the four additional repulsorlift engines that keep it afloat. These four repulsorlift engines produced a powerful field strong enough to repel any object on the craft's ventral section, but it could be penetrated by strong swimmers where it was non-existent.

By 137 ABY, the design was heavily modified. The version used by Darth Krayt's Galactic Empire could operate underwater and had shields. It included at least 6 laser cannons, including a rear double laser cannon to stem attacks from the rear, and was fitted with a launch bay containing at least five Shark underwater fighters. The new design looked similar to the old one, although sleeker in design. The command bridge was also replaced by another similar to an AT-AT's command bridge. Additionally, these vehicles were known to have transported Sith Lords on several occasions.