Catwalks
Wide catwalks are easy to move across and commonly appear in warehouses, engineering bays, and other large spaces. Narrow catwalks are common in starship interiors and other places where spaces are cramped, and they're difficult terrain. Unstable catwalks and narrow catwalks that lack railings likely require creatures to Balance to cross safely. Creatures that fall off or are pushed off a catwalk take falling damage.
Characters on a catwalk can usually Take Cover. Depending on the catwalk's construction material and rails, as well as the positioning of creatures, catwalks could provide cover automatically.