Departmento Munitorum Combat Diver Corps

Colloqually known as the Frogmen Corps the Departmento Munitorum Combat Diver Corps is a special company-sized infantry formation assembled directly by Departmento Munitorum.

Frogmen
Frogmen, or combat divers, are specially trained and equipped troops to perform underwater operations.

Worlds of origins
Frogmen companies are trained and assembled on numerous worlds across the Imperium. Even with their special status as the "best-of-the-best", Departmento Munitorum Corps are not Tempestus Scions and do not have access to such high-tech armory. These worlds are used to train the special frogmen troops:
 * Truman's World - ocean world in Vigilius sector, Ultima Segmentum

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Equipment
Departmento Munitorum Corps have more uniform equipment than regiments in general do. All frogmen companies can be expected to have the following equipment with them.
 * Amphibian autoguns - patterns and variants are innumerable. However, most underwater autoguns use small, steel darts as their ammunition and are known as "needlers" (not to be confused with Imperial needle weapons).
 * Sabotage equipment - frogmen are used for sabotage, infiltration, scouting and even assassination. They carry various sabotage equipment including, but not limited to, explosives and naval mines.
 * Rebreather - rebreathing equipment allows frogmen to dive without air bubbles revealing their position.
 * Waterproof Imperial Infantryman's Uplifting Primer - Imperial Infantryman's Uplifting Primer Mark VII is a waterproof version of this must-have trooper equipment and is issued for everyone within the frogmen companies.

Underwater vehicles include various models and patterns of swimmer delivery vehicles as well as sub-marines of various sizes. Depending on the mission at hand and the purpose of the company they might be equipped with anything from handheld swimming assistance devices to underwater torpedo platforms.