Find Fibblebrap in the Creep of Corathus

Find Fibblebrap 1: The Mines
Enter the instance, you will find a stone on the ground pick it up, it's the memory fragment you will need later. Make sure everyone is in the elevator. Hail the clockwork gnome to go down. Kill the greenies, and go down the elevator again. You will NEED a good puller, the blue con adds are NOT MEZZABLE. You will need to clear to the right, or the southern most room, you will find an Alpha Larva, kill it and loot the meat. Then go east to the South Eastern most room, there you will find a giant yellow conned clockwork by the name of Clicktok, hail him to get the gem. Exit the Zone. Return to Bellfast, and one person needs to turn in both the gem and memory sphere.

Note: The larvae runs are mezzable.

Find Fibblebrap 2: Lost Caverns
Head to the Lost Caverns.

Located in Stoneroot, in the western circle, in the center where the werewolves are located, there is a cave, enter it and go to the left, you'll see a temple looking front, with a wooden door. Click the door to enter the Lost Caverns (Careful when heading there, there are see invisible in the tunnel, and the wolves hit for 600's fast, so you may need to rush the zone).

The Zone is FILLED with undead, and a few werewolves. The named, Captain Therimal, is in the west part of the zone, and takes some fighting to get there. The undead are stun immune, adds very easily, and come in packs, so make sure to bring a chanter or a good puller at the very least. Repops are fast, so you want to just plow right through them. Once you're to the named Captain Therimal, kill him, he will have two zombie guards, dark blue, and a red con scholor, they are all gimp, and easily defeated, and the named Captain Therimal isn't too bad, he has an AE stun. When he's dead, loot Fibblebrap's gem and turn it in to Belfast.

Find Fibblebrap 3: The Hive
The instance is located in the hive, at the one called Living Larder. It's the same one as rescue the gnomes from Dreadspire access, the one inside the third hive tower. Follow your compass if need be.

Once inside, clear the west portion of the zone. In the west portion of the next room, to the north is the named, red con, and hits hard and fast. To the south, is the exit. Clear both rooms. When that is done, attack the named, at 35% he will run and exit to the south, to another instance. Zone in, you're in the sheilskin instance at the very top. This layout is the same as Rescue Cicero, except you're on the top, not the bottom. You can fight down, or levitate down. Once you at the bottom, clear the roamers and a few mobs around the bottom of the room. Pull the named and kill him, he's rather simple, no sneaky tricks. Once he's dead you get a chest reward. Loot the gem from the body. Turn it in to Bellfast to complete.

Find Fibblebrap 4: The Korlach
Go to Ruins of Illsalin. Go to the Wallwatcher's Citadel, which is probably marked on your map, and probably came across this if you did the Slipgear quest. Inside the building if you go up, you will see a cocoon in the corner.

To open it, clear the room where it's at, the bottom and the bridge of dranchinds and anything else that's KoS. Once cleared /open the cocoon, and a sporilli pops out by the name of Neran Sporestomp. Invis vs Undead, and follow it, it will head down the ramp, south, out the room, across, the bridge, into the next room, up the ramp, and outside, all straight south. Outside you will come across a broken bridge, stand in front of him, and you will be thrown all the way to the other side, if you miss it, you're going to have to find other means of getting across. But during the run, he will probably agro drachnids, you don't have to assist to save him, chances are if you do you'll agro the train of drachnids on him.

Once across enter the door behind you by clicking, you will enter an instance similar to the Praetorian Guard, which is the same layout as 70.2 of spell progression. From here you will need to find the alchemist. To find/pop him, you must clear and crawl your way through, because there will repops. Crawl your way though to the center of the zone, where you see the big pool of water. Go down, and fight your way through the underwater tunnels. At the end you will come across and underground cave. Clear the room of all mobs in the underground cave, and you will pop the alchemist, he will pop in the room, he's a red con, and very easy, he just has a ton of HPs. Kill him, loot the gem, turn it into Bellfast to complete your mission.

NOTE: This mission MAY be timed upon zone in, believed to be one hour, to kill a certain amount of mobs to pop named.

Find Fibblebrap 5: The Rescue
Destroy ten creep reaper guards. Destroy the hurt machine. The hurt machine is located in the eastern portion of the zone, if you have a map, it's in the northeast part of the zone, at the dead end. The named is rather easy. Recover Fibblebrap's core, from the hurt machine. Then turn in core to Bellfast to complete the arc.

NOTE: This mission is OPTIONAL, you do NOT need to do this mission to get your skull/resist clicky, but you will complete the arc, and a small group reward.