She was a highly dexterous mage, and skilled in making poisons. She modified her magical curdled death oil to incapacitate rather than kill, and to evaporate into a breathable substance when exposed to high temperatures.
Reptilla and her small dragon familiar, Thsst, dwelt in a cave on the sunnier side of the Dragonspine Mountains. From here, they ambushed animals and lone travelers and used them for Reptilla's experiments with poisons. She daubed her curdled death on rock faces along mountain paths around her lair. As the stone warmed under the daylight sun, the curdled death activated and knocked out passers-by, so she could take her victims alive.