[quote=So Boerd]
"their inability to breathe oxygen in the same quantities as other the creatures of the world outside their lands"
[/quote]

"One of the most important plants to the Dominion is the Harkti bush, a shrub that produces foliage that is capable of trapping oxygen within it's fibers and filtering through gases which the Tarix-Na can breathe. Drying the leaves allows longer use of the plant, as well as enables the Dominion to store supplies of the plant for long journeys. Using this plant, the people of the Dominion are able to leave their lands and travel the world for so long as they have a supply of the Harkti bush's leaves."