This instance may be done Solo-only or in a Small Fellowship.
- Upon entering the instance, you have to fight a couple Flood-lizards and Scared Flood-lizards. Moving forward, there is a gate in your way, but to your right (east) you see a set of broken, tilting platforms.
- Climb the platforms, defeating lizards; turn the wheel at the top, and then go back down the platforms. Go through the now-open gate to the north and down the stairs. On your right at the bottom of the stairs, you see another closed gate (with a lever inside).
- Head south in the opposite direction from the closed gate. You will come to a canal leading to another set of tilting ramps on the right (west). To the left (east) is a bridge, but there is a gap between you and the bridge that you cannot cross.
- Climb the ramps to the west, pull the lever at the top, and head back down the ramps. The bridge to the east has now been extended; cross over and head down the canal to the Cave Rock-worm pacing in front of a closed gate.
- Defeat the rock worm and follow the ramps down and around. At the end there will be a lever in front of you and a wheel to your left (south). Use the wheel and then the lever, then HURRY back to the gate by the defeated Rock Worm. If you don't hurry, the gate will close and you will have to use the wheel and lever again. Head in the tunnel, defeat the two lizards, then drop down the hole in the floor. Run ahead (west) to kill the Rock Worms, and pull the lever there. The bridge to the south will extend, but no need to cross it.
Note: if you get defeated after this point, you will have to click the wheel and lever again to continue back down.
- Turn north and enter the cavern. On your left (south) before the lizard and worm there are stairs leading downward. Go down and head south down the hallway, where you will find Spit Tail. Defeat him, then head east down another hallway, where you will encounter a Lesser Caerog. Defeating him will cause the wall to crumble, and below you will be some platforms. Jump down the ramps and you will come to the Relic of Gorothul. Click on it to destroy it and advance the quest.
- Caerlûg's lair is riddled with thumping piston-like cylinders, and he does knockback. Therefore, be sure to approach him straight-on, keeping your back to the tunnel from which you just arrived.
You may be able to avoid the knockback if you see him raising his arms in warning, but unless you run directly backwards toward the tunnel, the risk of being knocked under the pistons probably outweighs the possible benefits.
NOTE: If he is not defeated quickly enough, he may stop fighting and heal; in order to re-aggro him to stop the heal, you would have to follow him to one side of the room and pull the nearest lever. This tip was observed for the three-man instance and may not apply here.
- The instance closes IMMEDIATELY on the defeat of Caerlûg (10 seconds).