My interpretation of whatever monster I feel like talking about, primarily from the 1st ed AD&D Monster Manual and Fiend Folio, but not limited to them, treated in a way that deals with the stuff I find interesting. That is: ecology and culture, if applicable. Stats can go hang.
As an Australian, I know that the Echidna is a creature that was ridiculed as being impossible when it was discovered. An egg laying mammal with the duck’s beak? It had to be the conn of the century. And yet, strangely, I’ve seen them for real, and they are real, so get stuffed you conspiracy theory types that attribute anything unusual to human deceit.
The REAL Echidna was one of the daughters of the Greek Titans, and she was the mother of many of the fascinating monsters of that mythology, such as Cerberus the many-headed guard dog to Hades.
What is really fascinating is that Echidna (not THE Echidna because there was only one of her) has almost exactly the same description as the Hindu Naga.
Were I a psychologist I would claim that there is something perverse in the heart of man that imagines a half woman-half snake. But I’m not, so I’ll just say that it’s mighty interesting… that’s all.
Naga, and therefore the Queen of Naga, Echidna, are entirely normal creatures, though very powerful. They do not appear to be supernatural in terms of what they can and cannot do, though they do have magical powers.
Their torsos resemble humans, often beautiful females though that might just be the conceit of the adventurers that have faced them and survived. Their lower portions resemble mighty serpents. A simple calculation suggests that these serpent portions would be long and very strong.
If you, like I, were influenced by Ray Harryhausen, you are probably imagining Medusa as being part of this family, but there is no primary evidence that the bottom part of Medusa was serpentine – just her hair. So she can be ignored, along with her look-to-kill technology.
Nagas, and Echidna, are an extraterrestrial species that visited this planet many thousands of years before today. Their original technology and feats are recorded in legend. For game purposes, Naga, or their Queen, Echidna, should be presented as extremely powerful creatures that have their own goals for gathering power and technology in order to rebuild the means to get off this primitive shit-hole. They are not simply monsters occupying a room or collecting interesting paintings. They are sophisticated beings working to a plan and viewing humanity as annoying monkeys