The thing you must remember about the universe of Warhammer 40k is that it isn't ours, despite some similarities. One key difference is that, unless proven otherwise in an Event Horizon-esque experiment, I'm pretty sure our reality doesn't float upon a gestalt ocean made up of the most horrifying emotions from a multitude of species. In this fictional universe, traversing this galaxy means sailing through those terrifying depths. In Warhammer 40k Rogue Trader you do so in your voidship - which is the focus of the new DLC, Void Shadows, and you can play it now.
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