|Peryton by Una Woodruff in the book Inventorum Natura|
I'm pressed for time so today will be a short post.
The Peryton is one of my favorite D&D monsters yet it is so often underused. To me the Peryton makes for an excellent random encounter in the wilderness for two main reasons. First off, many animals in fantasy are portrayed as benevolent majestic creatures, the Peryton of course is not but your players likely don't know that. Secondly, Perytons are a great alternative to the Griffin and a perfect lead-in to "Mad scientist is splicing together animals in woods" if you're avoiding Perytons as strange elder beasts mythology.
For the first reason let's explore why these guys are great for a random encounter. Your players likely don't know about these obscure creature as they aren't very prominent in D&D or common cultural mythology. It has the body of a deer and the wings of a bird, not too frightening. If anything it might appear inviting for any would be naive druids. Contrast that with the Griffin who has the body of a lion and the head of an eagle, quite a vicious beast. So your players will more than likely approach this creature out of curiosity or friendship. Unfortunately for them, Perytons crave human hearts. Rather than play them conventionally, using trickery regarding there human shadows, I think it'd be best to have the Peryton appear docile until it is ready to strike and carry off it's prey (a straggler.) Now your players will have a newfound wariness of woodland creatures and you just got another excuse to throw a weird magical beast into your game of sword and sorcery. Hurrah!