There are 8 different types of rare elite you can face, and roughly 8 in each zone.
They vary in level by zone and cap out at level 1 with 4 million HP.
They currently give around 200-400k exp (level depending) and have approximatly a 30 minute respawn time.
They do little damage through their auto attacks, but be ready to heal if you start taking their special attacks. Some of them like Nanners and Ai-ran can be a nice rewarding challenge to solo.
When ever possible it is always best to fight them in the open, you'll want the space to avoid their aoe.
They range in difficulty depending on your class and the type of enemy, from the Mogu Sorcerers being trivially easy, to the Pandaren being significantly harder and almost impossible without a good interrupt or stun.
The bold-fonted abilities can and will kill you if you don't move out fast enough. Some are based on HP percentage so you don't ever overgear them.
Hozen:Bananarang Creates a whirling banana that spins along the ground away from him in a line and then back again causing Bananarang to anyone in it's path.
Toss Filth Increasing damage on you by up to 11%
Going Bananas Causing him to jump around the area dealing damage with Going Bananas if he lands on you. Will rarely hit you if you're outside, but if you're both in a room it's likely to kill you.
Jinyu:Waterbolt Basic spell damage that needs to be soaked (do not interrupt)
Torrent A cast time and then a channeled attack that will kill his main target unless major cooldowns are used, needs to be interrupted. (Takes 25% HP per second)
Rain Dance A channeled aoe that throws out blobs of water in the area around him, simply run away from them to avoid the damage, or stun him mid cast.
Mantid:Tornado Creates a tornado where you're standing that whirls around near it's spawn point . Needs to be moved away from otherwise it inflicts Harsh Winds.
Windsong Buffs himself doing more melee damage and preventing kiting (can still be stunned)
Blade Flurry A brutal conal aoe with a short cast time before it starts. Needs to be run from or stunned to stop.
Mogu Sorcerer:Dark Bolt Auto attacks with his wand instead of in melee.
Shadowbolt Shadowbolt main attack, can be soaked or interrupted.
Voidcloud Persistent shadow aoe cast on the floor on the players position.
Mogu Warrior:Devastating Arc A 180 frontal attack, if you're in melee you can stand behind him, ranged can run away.Summon Quilen Summons an add to assist him, has little health and does minor damage, can be killed or cc'd untill it disappears.
Titanic Strength A periodic enrage buff cast on himself increasing damage by 5% and stacking.
Spinning Crane Kick Cannot be interrupted other than stunned. Causes Spinning Crane Kick to anyone still in melee.Chi Burst (2,450% ~300k at level 91) Used if you are more than 15 yards away. Run back in after crane kick (do not waste interrupt).
Healing Mists Must be interrupted or stunned / cc'd.
Saurok:Vicious Rend Stacks and does damage over time.
Vanish Must be hit as he stealths to stop him using Smoked Blade.
Smoked Blade Used when he comes back out of stealth.
Grappling Hook Used if you are more than 20 yards from him.
Yaungol:Yaungol Stomp Small aoe stomp for heavy damage, simple to move from.
Rushing Charge Charges his target if they run more than 20 yards away.
Bellowing Rage Increased damage but slowed movement speed, can be soaked or run from.