Uranium

As the head of the mining operation, Uranium manages the miners and engineers in the Thorium Caverns. She's rather no-nonsense and very strict about safety measures. She's a motherly figure who is pretty much the only non-serpentine creature who Nei tolerates. Her ownership of Hotline, her amphithere who alerts her to hazardous gasses, is probably the only reason he even bothers with her, though he has taught her the names of his snakes, most of which are something along the lines of "Nssstu" and "Tssstssa". She might have heard him talk before, but she denies it. As a nature dragon, she's rather sensitive to toxic gasses, so Hotline helps her sniff them out and warn the other dragons before someone gets hurt. She doesn't tolerate horseplay in her mines and is known to grow vines as shackles and whips to keep her dragons from getting someone killed. In the end, she's just looking out for the safety of her dragons and knows well the dangers of radioactive ores.