"The Quest of the Queen's Tears" by Lord Dunsany

Serpents of Licantara - as best I can tell, this is a made-up thing. At least, google doesn't know about it outside of this story. So I am left with no hints on how to pronounce Licantara.

The picture used is an illustration by Sidney Sime in the 1912 edition of "The Book of Wonder".

To follow along: https://www.gutenberg.org/files/7477/7477-h/7477-h.htm#THE_QUEST_OF_THE_QUEENS_TEARS

Sounds like this Queen was quite literally a sociopath. These suitors should be glad they failed to win her hand, they dodged a real bullet. I mean, I guess in the sense that marrying a Queen gives access to power and prestige and wealth, yeah, that's all great, but having to spend the rest of your life married to a sociopath doesn't sound real appealing regardless of the upsides.

But then, those princes who wanted a quest of murder and mayhem, sounds like those guys were psychopaths, so this may be one of those cases where there are no good guys, only bad guys all around.