Princess Tempestria is part of the periodic Elemental Invasions. When she appears, she will yell, alerting everyone in Winterspring she has spawned. She spawns amidst a host of water elementals and is constantly escorted by some of her guards.
Princess Tempestria yells: If you mortals are all so craven, this will be much easier than I thought!
Patch 1.4.0 (2005-05-05): Added.