This is a 3-man radiance armour instance in the Waterworks in Moria which grants multiple Medallion_of_Lothlórien for the +15 radiance armour set. Challenge mode is to defeat the final uber-caerog boss and also to defeat either the "3 at once" caerog room or the "12 in a row" caerog room.

The First Wheel

After you enter, at the end of the first aqueduct, you will encounter 2 big lizards and one small lizard. The big lizards are summoners and will summon tiny lizards. There is a gate ahead (the First Gate), so head to the right (towards the waterfall) and continue up the wooden ramps towards the First Wheel which unlocks the First Gate. After turning the wheel, retreat back to the beginning then head North through where the first gate was and go down the stairs. There is a flower here.

The First Lever

This is sort of a mini repeat of the first part, but there is a group of 5 lizards at the top of the ramp, which are mostly hidden from view and easy to aggro. This is the largest group of lizards that you have faced so far (or will face) and new groups often wipe here. At the top you will find the First Lever. This lever is an important lever and you will likely be coming back to this lever. More will be said about this lever in the appropriate gates. Retreat back down and cross the new gate-bridge.

The Locked Room

There is a patrolling rock worm here, guarding a gated off room with a flower in it and a rabbit hole. Continue past this locked gate, passing a flower, to kill a set of four linked lizards. There is a wheel and a lever here. The lever opens the locked gate that you just passed, but before sending two of the party members through, go down and kill the single lizard below. Retreat back and send two party members through the locked door. The third member should then go back to the bottom. If the two members who went into the locked room want the flower then they will have to kill the two summoner-lizards here, otherwise they can simply jump down the rabbit hole.

The Optional Locked Room

The two party members who entered the locked room should proceed straight out to the West, possibly encountering one or more rock worms, to pull the lever to allow the 3rd party to cross the new bridge and rejoin the party. Kill the rock worms here. There is another locked room to the West with a flower in it. It is opened by pulling the First Lever, but if you pull the First Lever at this point (since it retracts the gated bridge) you cannot get back down here (there is a kill spot in mid air which kills you if you attempt to jump down here from the aqueduct above). Continue on to the stairs.

The Stairsets

The stairs down take you to the rest of the level. There are two stairs up, the front set and the back set, with the front set being right by the stairs down. The front set takes you to a flower and allows you to get at the First Lever (which is how you get into the optional locked room). The back set has a lever which opens the "12 at once" room -- more will be said about this in a moment. At the bottom of the stairs down is a gate which is unlocked by the First Lever. If you pull the lever to get into the optional locked room, you will have to pull it again to close the optional locked room and continue to Spit-tail.

Spit-tail

Spit-tail is the first boss of the instance. He has two lizard adds who will periodically respawn. If he is pulled near the stairs down to his level, he resets. He has a rather hefty frontal cone acid AoE which applies a poison DoT which must be removed quickly. His chest is off to the East, near a caerog and a lizard (be careful not to aggro them until you're ready to fight them). A rabbit hole down is just beyond this caerog. To the West is the "3 at once" room and to the South is the "12 in a row" room.

Optional Challenge Encounter

"3 at once"

The gate to this room is triggered by the First Lever. One person needs to run back up, pull it to open the door so that the other two people can go into the room, then pull it again to close that gate and reopen the gate to Spit-tail's area. This person should then head back down to the "3 at once" gate. There is a lever just inside the room which will allow the people in there to open the gate and allow the 3rd person to enter the room. Run up to a caerog when you're ready and all three will attack at once. Kill them all, then head East for the final boss.

"12 in a row"

The bridge to this area is back at the top of the back set of stairs in the Stairsets area. One person needs to go pull it while the other two party members stand ready, as the gate will only be extended for a short time. Once someone has crossed, they can pull a lever on the opposite side to allow the 3rd party member to join them. In this room, 12 caerogs will attack in a row, two at a time. The next caerog will not attack until the first of the set has died, so by not killing the caerogs in order the group can have a "resting time" with only one caerog attacking for a moment.

The final boss

The rabbit hole East of Spit-tail's area drops down a series of boards to a hallway. Near the end of the hallway, just outside the boss's room, is the glowing ball of blackness which completes Vol._II,_Book_8,_Chapter_4:_A_Relic_in_Nalâ-dûm. There are pistons in the boss's room which will pound down -- Caerlûg, the boss, ignores all pistons, but they can block line of sight and they will stun you if you run under one as it comes down or you are knocked into a piston. Position yourself accordingly. Caerlûg occasionally raises his arms and holds them. When he brings them down, he will do an AoE line of sight knockback for 1k damage. If you are punted, your damage will be wiped. He will then randomly charge someone, if there is someone out of melee range, and attempt to hit them for 2k damage (poisoning them).

Periodically, Grawulun the Caerlûg will stun all three player characters and run off to a corner to heal. Pull the lever on the North side of the chamber which is on the same side that he is on to switch which pistons are pounding and to wake Caerlûg up. If you are quick and near the lever, he will only heal 1k morale.

When he dies, his chest and the Challenge chest is yours! There is also a third chest which is a quest objective for The Water-wheels: To Stagnant Nalâ-dûm.

See Also

• YouTube video walkthrough