The L'Dira are an alien race that carries its skeleton on the outside of its body. This exoskeleton helps protect them from the sudden pressure changes and periods of hard vacuum that occur on the surface of Xargos, their homeworld. This exoskeleton allows them to seal their joints, giving further protection. The L'Dira live in hermetically sealed cities built to withstand the tides of vacuum, and their society has grown up around the intense mathematics needed to accurately predict the vacuum tides. This had given the L'Dira the reputation of of being proficient mathematicians and strategists. The L'Dira also have a fairly advanced technology, and are respected starship builders in most sector of the galaxy.