In Warhammer 40,000
In Warhammer 40,000, the term "space hulk" is used to refer to any massive derelict space ships. Space hulks may house more than just Genestealers; other threats aboard can include followers of Chaos (who do not mind traveling in the Warp), Warp Daemons, and Orks who use space hulks as their "standard" method of interstellar travel. As a corollary, Space Marine Terminators have also fought Genestealers in other settings with narrow corridors in more locales than just space ships; for instance during Hive Fleet Kraken's invasion which instigated an uprising on the Imperial planet Ichar IV, Ultramarines Terminators eliminated a Genestealer Cult in a crypt beneath the rebel-held cathedral.
Space Hulk was one of the first introductions of Genestealers, and although subsequent games have included them as part of the overall Tyranid army, Genestealers can still have a sub-army as in a Genestealer cult.
Space Marines Terminators were originally only used in Space Hulk-type scenarios and not the open battlefield, however demand was high enough that rules were added for their deployment in conventional Warhammer 40,000 battles. The plastic five-man Terminator squads with standard armament (4 carry storm bolters while 1 has the heavy flamer, 4 have power gloves except the sergeant who has a powersword) were initially only found in the Space Hulk board game, but they were released as a separate box set in 1997 for players who wanted them for Warhammer 40,000 battles. Previously, the only standalone Terminators were available as expensive metal figures in box sets and blister packs. The metal Terminators continued to be sold alongside their plastic counterparts for some time as they contained exclusive weapons and ornaments not found in their plastic counterparts, such as assault cannons and lightning claws, and Chapter-specific sets for the Dark Angels Deathwing and Space Wolves Wolf Guard. In the 2000s, however, Games Workshop phased out metal Terminator figures altogether, and the plastic Terminator box sets now contain a variety of weapons.
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