an Algerine-class minesweeper launched in 1942 HMS Hydra (A144), an oceanographic survey vessel launched in 1965 Hydra-class minelayer, a class of Dutch 1910s minelayers Other uses The Hydra, a literary magazine Hydra (association), a German self-help and advocacy group for prostitutes Hydra (video game), an arcade and Atari Lynx video game Hydra game, a concept in mathematical logic Hydra Market, a Russian language dark web marketplace that facilitated trafficking of illegal drugs as well as financial services Hydra the Revenge, a roller coaster at Dorney Park in Pennsylvania, US Hydra 70, an air-to-ground rocket Hydra Technologies, an unmanned aerial vehicle firm Hydra Trophy, a trophy of the roller derby WFTDA Championships Hydra, a wireless station during World War II at Camp X Operation Hydra (Yugoslavia) Operation Hydra (1943) See also Greek ship Hydra, a list of Hellenic Navy vessels HMS Hydra, a list of British Navy vessels Hydro (disambiguation) Hydrus, a small constellation in the deep southern sky Ghidra, reverse engineering software