Isle of Thunder Rare Spawns

There are a total of eleven rares on the Isle of Thunder. Ten of them are required for the achievement Champions of Lei Shen. They are all on very short re-spawn timers that seem to be between 30min to an hour, and certain rares become available after unlocking different Stages of progression on the Isle. (More info on that below.)

All of these rares (minus Ra'sha) share the new tapping system introduced in patch 5.2, where so long as you participate in killing the rare you will have access to it's loot. As more and more people join in on the fight, the mob's health pool will increase with each additional player. All in all, I think this new system is great, as it gives players around the Isle more time to get to each rare once it's been called out.

Each of these rares is guaranteed to drop a Tome of Valor worth 15 valor points each time you kill them. They will also drop a single Shan'ze Ritual Stone and a Key to the Palace of Lei Shen for an individual character once each week (so long as you haven't already looted the key elsewhere). Obtaining three ritual stones will unlock the group quest Setting the Trap, which will then lead to the weekly group quest Champions of the Thunder King. Obtaining a Key to the Palace of Lei Shen will unlock the weekly solo scenario Troves of the Thunder King where you will have five minutes to grab as much treasure as you can before the clock runs out.

These rares also have a very small chance to drop the item that begins the questline for warlocks to get their green fire; Sealed Tome of the Lost Legion. The tome seems to be roughly a 2-3% drop chance off of any one of the rares (minus Ra'sha), and can only be looted by warlocks. When combined with a Healthstone the item becomes The Codex of Xerrath, which starts the questline with An Unusual Tome.

So without further adieu, here are each of these rares listed below in the order they became accessible on the Isle. If you scroll further down the page I also have a slightly more up to date map showing exactly where they can be found.

Haywire Sunreaver Construct
NPCID: 50358
Coordinates: 48, 85
Location Description: Running along the shores in southwestern Ihgaluk Crag
Base Health: 10539k
Notable Loot: Sunreaver Micro-Sentry

Abilities: Haywire: Go Haywire! Deals 18500 to 21500 Nature damage to all enemies within 40 yards every 1 sec. for 20 sec and increases movement speed by 100%. (Ranged players can still dps him and not get hit, so long as you stay right at about 40 yards. Others should be able to heal through it. If you don't have heals, I recommend getting away from him for the 20 seconds he casts this.)

Ku'lai the Skyclaw <Ward of Beasts>
NPCID: 69996
Coordinates: 36, 82
Location Description: Patrols the beach south of Za'Tual
Base Health: 7167k, Pet: 1969k

Abilities: Bladewind: Spin around in a whirl of blades, inflicting 46250 to 53750 Physical damage to nearby enemies every 1 sec. for 10 sec. (This is easily avoidable  Simply move out of melee range when he starts spinning.)
Leaping Rend: Leaps at the target and slashes, causing the target to bleed for 20000 Physical damage every 1 sec. for 10 sec. (Ranged players - be sure to stand fairly close to him, he only seems to use this ability when your far, and it HURTS.)
Pet (Tamed Pterrorwing): Spirit Bond (So long as his pet is alive, Ku'lai will take half damage. KILL HIS PET FIRST.)

Progenitus <The Firstborn>
NPCID: 69997
Coordinates: 50, 74
Location Description: At the very top of the highest peak in Ihgaluk Crag. You will need Skin of the Saurok disguise to reach him.
Base Health: 7588k

Abilities: Evolution: Increases all damage dealt by 10%.
Mutagenic Burst: Inflicts 46250 to 53750 Nature damage to all enemies within 5 yards and knocks them up.
Unleash Blood: Inflicts 46250 to 53750 Nature damage to all enemies within 10 yards and knocks them back. (This ability can be a real killer, and quite literally because it can knock you off the mountain. Either stun him while he's casting it and run away, or position your back against the big dinosaur head.)

A note for pet classes: Use the "move to" option to keep your pet on the top of the mountain, especially if your pet has aggro. You can also put your pet on passive to keep Prog from chasing it down the mountainside if someone else is there tanking.

Mumta <Thief of Souls>
NPCID: 69664
Coordinates:
Location Description: On the top floor of The Hall of  the Grand Imperion in the Court of Bones.
Base Health: 6745k

Abilities: Darkest Darkness: Reduces healing taken by 99% for 20 sec.

Spirit Bolts: Deals Shadow damage to all nearby enemies every 0.5 sec.

Vengeful Spirit: Summons a vengeful spirit to assist the caster. (This is by far the most important thing to look out for while fighting him. If the vengeful spirit is coming after you - RUN AWAY. The spirit hits very very hard, but it can be kited and slowed and will eventually de-spawn.)

Goda
NPCID: 69998
Coordinates: 53, 53
Location Description: Standing inside of a tree in northeastern Diremoor, just south of the wall separating the next part of the zone.
Base Health: 10539k

Abilities: Crystalline Shield: Protects the caster in a crystalline shield, reducing magical damage taken by 10%. (This ability stacks, but can be purged, dispelled, etc.)
Shell Spin: Spins around for 10 sec , inflicting 92500 to 107500 Physical damage every 1 sec. to enemies within 10 yards and knocking them back. (This hits pretty hard, but is super easy to avoid. Just run away when he starts spinning.)

Al'tabim the All-Seeing
NPCID: 70000
Coordinates: 44, 31
Location Description: On the Northwestern shore next to a large cauldron.
Base Health: 6323k

Abilities: Meteor Shower: Summons a shower of meteors, dealing Fire damage at the impact locations.
Omen: Inflicts 400000 Shadow damage after 2 min. Leaving combat cancels the effect. (This debuff isn't much to worry about if multiple people are killing him and he goes down fast. If you are soloing him however, and your dps isn't high enough this debuff can be deadly. I imagine classes with some kind of damage absorption would fair better against this guy solo.)
Shadow Bolt Volley: Hurls missiles of dark magic, inflicting Shadow damage to nearby enemies.

God-Hulk Ramuk
NPCID: 69999
Coordinates: 60, 50
Location Description: In front of the stairs leading down to the gate to Stormsea Landing. (Becomes accessible during Stage 3)
Base Health: 8431k

Abilities: Blessing of Thunder: Call for the blessing of Lei Shen, increasing damage dealt by 100%, damage taken by 50%, and reducing movement speed by 50% for 15 sec.
Crouch: Crouch down into a ball, reducing incoming damage by 50% and healing for 5% of maximum health every 3 sec. for 20 sec. (This ability CAN and SHOULD be interrupted.)
Pound: Pound the ground, inflicting 138750 to 161250 Physical damage to enemies within 5 yards of the impact and knocking them back. (This has a cast time, just be sure to run away the moment it starts.)

Lu-Ban <The War Crafter>
NPCID: 70002
Coordinates: 54, 35
Location Description: At the Thunder Forges, standing in front of a large mogu statue and table with mogu weapons on it. (Becomes accessible during Stage 4.)
Base Health: 6745k

Abilities: Skyforged Hammers: Skyforged hammers inflict 27750 to 32250 Nature damage on melee attack.
Storm Bolt: Fling a hammer at a distant target, inflicting 138750 to 161250 Physical damage and stunning them for 3 sec. (He casts this when your further than 15 yards from him, so ranged players just don't stand too far away.)

Backbreaker Uru
NPCID: 70001
Coordinates: 50, 25
Location Description: He patrols the back entrance of the Lightning Vein Mine. (Becomes accessible during stage 4.)
Base Health: 9275k

Abilities: Break Spine: Crush the target's spine, rooting them in place and reducing their chance to dodge and parry by 100% for 15 sec. (He uses this on his current target.)
Massive Stomp: Deals 185000 to 215000 Physical damage to all enemies within 30 yards. This ability only affects targets that are on the ground. (Combined with Break Spine, this ability can be very painful. All you need to do to not get hit is jump before he gets the cast off. If your his main target and your pinned down though, get ready to heal or use some defensive cd's.)

Molthor <The Gatekeeper>
NPCID: 70003
Coordinates: 62, 48 & 58, 35
Location Description: He has two spawn points. One of them is behind God-Hulk Ramuk on the overlook at Stormsea Landing. The other is in the back of the Swollen Vault. (Becomes accessible during stage 5.)
Base Health: 8010k

Abilities: Horrific Visage: Strikes fear in an enemy, causing it to flee in terror for 8 sec.
Scarab Swarm: Summons a bevy of scarabs to attack the enemy. (These can easily be aoe'd down.)
Thunder Crush: Crush enemies in a cone in front of the caster for 231250 to 268750 Nature damage. (Move out of this when you see it on the ground. It hurts. It looks like a grey thundercloud floating just above the ground.)

Click to Enlarge

Ra'sha (NOT part of the Champions of Lei Shen Achievement)
NPCID: 70530
Coordinates: 39, 81
Location Description: In the back of the cave by the water where the skeletal raptors are located. The cave is guarded by two elite Zandalari Execution Guards.
Base Health: 4075k
Notable Loot: Ra'sha's Sacrificial Dagger (Ra'sha does not share the same "tapping system" as the other rares in this zone. The first person/party to engage him will be the only ones able to loot him.)

Abilities: Bloodbolt: Inflicts damage to an enemy and reduces its movement speed for 4 sec.
Bloody Strike: An instant attack that deals 110% weapon damage.  Increases attack damage by 5%, but reduces chance to hit by 5%. Lasts 15 sec.
Mark of Blood: Place a Mark of Blood on an enemy.  Whenever the marked enemy deals damage to a target, that target is healed for 4% of its maximum health. Lasts for until cancelled. (Simply stop hitting him when he puts this debuff on you, otherwise the fight will go on forever.)

Although he isn't part of the Champions of Lei Shen achievement, he will still drop a guaranteed Tome of Valor and potentially a Shan'ze Ritual Stone. Unlike the other rares on the island he could also potentially drop a Small Bag of Zandalari Supplies or a Big Bag of Zandalari Supplies.

Helpful Addons:

IoTRares

Ever wonder what that addon is that has people calling out which rare is up, with info on the rare's location and % health left in general chat on the Isle? That is the addon IoTRares. Not only will it call out in general when you've targeted a rare, it also keeps track of when you've last seen each rare to more easily keep track of which ones will likely be spawning in next. Here is an example below of both what you'll see called out in general chat, and the timers for when each rare was last killed that only you will see.

What is nice about this addon is that it's not as "spammy" as you'd think it would be. When several people in an area working on one rare all have this same addon only one person will call out the progress on that rare in general. I've found this addon very helpful, as I know many others on my server have as well. You can download this addon from Curse. 

TomTom

If you use tomtom, you can simply add these waypoints to a macro for each of their spawn locations to show up on your map:

/way 35.0 82.0 Ku'lai

/way 51.3 71.2 Progenitus

/way 35.1 62.5 Mumta

/way 53.7 53.1 Goda

/way 61.5 49.6 Ramuk

/way 59.3 35.7 Molthor

/way 63.5 49.2 Molthor

/way 54.4 35.6 Lu-Ban

/way 44.7 29.7 Al'tabim 

/way 48.6 89.8 Haywire

/way 48.4 25.3 Backbreaker Uru

/way 39.4 81.6 Ra'sha

NPCScan

You can also add each of these rares into NPCScan, and it will pick them up so long as they aren't cached. You can add them quickly with these macros:

/npcscan add 50358 Haywire Sunreaver Construct

/npcscan add 69664 Mumta

/npcscan add 69996 Ku'lai the Skyclaw

/npcscan add 69998 Goda

/npcscan add 69997 Progenitus

/npcscan add 70000 Al'tabim the All-Seeing

/npcscan add 69999 God-Hulk Ramuk

/npcscan add 70001 Backbreaker Uru

/npcscan add 70002 Lu-Ban

/npcscan add 70003 Molthor

/npcscan add 70530 Ra'sha

Happy Hunting! :)