*Lightning Paw is a beautiful new spirit beast fox (added in patch 7.1.5) that can scale with your level starting at 17. She has multiple spawn points within bushes with blinking eyes around the western part of the zone. I wrote up a very detailed separate post on her here: Lightning Paw - New Spirit Beast (Fox)
Lupos (the level 20 white worg) does not have a unique skin, and beware of his melee attacks - this guy can give you Rabies! Naraxis (the level 21 red and green spider) is also not unique, but does have a pretty neat coloration in my opinion. Although her skin is fairly common now, during the Burning Crusade era the only mob that had this model and color was Terokkarantula in Terokkar Forest.
There are so many interesting rares in this zone. Each one really has their own story, and most of them even have their own titles. I'm not going to cover all of them, but I'd like to point out the ones I though were most interesting.
Watcher Eva <The Restless Dead> was the rare I found most intriguing. He is a non-hostile undead that patrols around the Tranquil Gardens Cemetery. His patrol route starts at the house of Blind Mary, then on to the campfire just outside, and then up to the graveyard. At the graveyard he will stop and kneel for a long while at one of the graves, when he stops at the campfire it almost looks as if he were preparing a meal. From there he walks back into Blind Mary's house and stands by the door where he states "They will pay for forsaking us. For leaving us amongst the beastly undead to rot..." When attacked he says "It did not have to be this way! I only wish to see my family again...to share with them this gift!" Poor fellow. I felt awful for attacking the guy.
There are two more undead rares in the zone; The Unknown Soldier and Eliza <Bride of the Embalmer>. The Unknown Soldier can be found kneeling over his own tomb in a secluded shrine near the mountainside in Beggar's Haunt. For an unknown soldier, he sure got quite the memorial (pictured at the very end of this post). I would love to know his story.