St. Elizabeth is known as the Wonderworker of Constantinople.
In sources outside of her Saint's life, she also has a dragon-slaying story attached to her name. This would make her the first female dragon-slayer (similar to the story surrounding St. George).
Whether or not dragons exist (I honestly don't know)--or whether "dragon" then referred to a creature different than what we think of nowadays--we can remember the allegory of dragons for evil; evil specifically (rather than generally). By St. Elizabeth's life and asceticism, she truly was in front-line combat with the enemies of our salvation; the fallen angels. And notice, all it took to subdue the dragon was the sign of the Cross (and she then placed her foot upon it's head).
Life of St. Elizabeth
A Dragon Mentioned, and Prayers to St. Elizabeth
(See how the dragon allegorically corresponds with spiritual warfare)