Zinhir eggs are laid by their mothers in the walls of the interior of The Volcano at the center of the island. The Volcano incubates them to hatching. The Science and Research Center in Ark City believes that high concentrations of sulfuric gasses, poisonous to Arkians, are required for Zinhir eggs to hatch. Humans, unless fully outfitted and insulated to properly travel to the innards of The Volcano, can do little to positively effect Zinhir egg laying or placement.
Despite the creature's ability to withstand extremely hot temperatures, one slip on the wall (when attempting to lay the egg) could cost them their life. They cannot survive in lava even though elementally they are thought to come from lava itself.
The flames that Zinhirs carry (rumored to be actual flames of The Volcano itself) are hugely representative of their actual personality and temperament: they are very hotheaded individuals with quick reaction times. They frequently fight with each other and respond quickly to all stimuli in their environments. They rarely reflect to become better or kinder creatures. The Science and Research Center in Ark City has estimated that approximately 27% of the total Zirhir population could be classified as "mad." Mad Zinhirs, essentially, will attack violently and without reason. They should be avoided.
Scientists have tried to pinpoint why Zinhirs are so intense as a species. They have theorized that Zinhirs are in a constant battle with themselves, tormented by the chains that bind them. Zinhirs are constantly trying to break their chains; they appear bothered by them despite the chains being with them from birth. Currently, ethical lab experiments are being conducted that attempt to break a Zinhir's chains. So far, there is no word of the results or if it has been successful.