This content is part of the Atlas of Discovery Expansion.

Underwater City

Introduction

This is a Barrier dungeon introduced with the Atlas of Discovery Expansion, there is a general guide to this dungeon and a more in-depth look into Barrier combat in general in this guide. This page will go deeper into combat options, including when Throne of the Herald Expansion is owned and already completed.
This guide is not meant for optimal kills per hour but instead focuses on easily obtainable ways ranging from just passed God Dungeons to having beaten Throne of the Herald to clear the dungeon effectively.

Requirements

Recommended

Level 99, Level 95, Level 75, Level 99.

The enemies, and especially the Nagaia hit very hard in this dungeon. A lot of damage reduction is required in order to idle this dungeon without dying. Alternatively, the player can return after having progressed through the Throne of the Herald expansion. Having more hitpoints or other damage reducing and damage inflicting bonusses can greatly speed up the clear times of this dungeon. Set 1 clears the dungeon roughly 27 times per hour. Set 2 clears it roughly 8.5 times per hour. (You can swap the weapon & summons in Set 2).

The Preferred Shield is Earth Layered Shield, however Devouring Barrier Shield can be used, once the upgrade item has been obtained from this dungeon. Clearing the Underwater City dungeon provides 1 Barrier God Shard every time it is cleared. These can be used to upgrade (B) god armours into their respective (C) armours. These can then be used to very effectively clear Crystal Depths for Crystal Binding Dust if the player hasn't already done this.

Equipment

Below are 2 sets, unlike the previous dungeons, you can't mix and match this dungeon. Set 1 is for post-TotH clears. Set 2 is for clears just before or after Impending Darkness Event.
Set 1 requires Level 120.
Set 2 requires a minimum of Level 99. Calculated at all combat skills level 99 in the Combat Simulator.

Set 2 can be all non-B upgraded Terran God Armour and it will only lower the Kills Per Hour by about 2 (from 8.5 to 6.5).

Item Slot	Set 1	Set 2
	Hood of Shade Summon	Terran God Helmet (B)
	Terran God Platebody (B)
	Terran God Platelegs (B)
	Terran God Boots (B)
	Gloves of Greater Shade Summon	Terran God Gloves
	Ancient Infernal Cape
	Amulet of Curse Totem Summon	Lesser Summoning Amulet
	Ring of Phantom Summon	Summoner's Blessed Ring
	Knight's Summoning Defender	Barrier Burn Shield
	Devouring Barrier Gem / Siphoning Barrier Gem
	Agile Wings Rapier	Infernal Claw
	Earth Layered Shield / Devouring Barrier Shield
	Fervor Scroll	Melee Hinder Scroll
	Spider Spectre	Tortoise Dragon

Prayers: Battleheart and Battleborn. Swap to Battleheart and Chivalry for Set 2.

Potion: Damage Reduction Potion IV

Point of Interest: Dark Waters

Agility

The Agility obstacles 9 or higher are not required, 8 and below are highly suggested (and simulations were done with those active).

Slot	Obstacle	Bonuses
1	Cargo Net	+3% Global GP (except Item Sales) +2% Fishing Mastery XP
2	Monkey Bars	-4% Firemaking Interval
3	Pipe Climb	+5% Melee Evasion +5% Melee Max Hit
4	Cave Climb	-40 Maximum Hitpoints +5% Ammo Preservation +5% Rune Preservation +5% Melee Max Hit
5	Cliff Balance	+20 Maximum Hitpoints +5% Ranged Accuracy Rating +2 Prayer Point Cost for Prayers +5% Magic Accuracy Rating +5% Melee Accuracy Rating
6	Lake Swim	+1% Damage Reduction +5% Damage To All Monsters +3% Chance To Preserve Prayer Points
7	Boulder Trap	-20% Chance to Preserve Resources in Skills
8	Raft Building	+20 Maximum Hitpoints +2% Damage To All Monsters +1% Damage Reduction
9	Ice Jump	+20 Maximum Hitpoints +5% Food Healing Value +5% Chance to Double Items Globally +10 Mining Node HP +10% Chance to Preserve Resources in Skills
10	Dragon Fight	-16% Auto Eat Efficiency -0.3s Monster Respawn Timer
11	Frozen Maze	+1% Damage Reduction -0.1s Monster Respawn Timer -3 Prayer Point Cost for Prayers -20% Rune Preservation -20% Ammo Preservation
12	Boulder Balance	-20% Global Accuracy +5% of Maximum Hit added to Minimum Hit -0.1s Attack Interval
13	Balance Trap	+10% Agility Interval +5% Chance to Double Items Globally -30% GP gained from Agility
14	Freezing Climb	+30% Accuracy Rating +30% Global Evasion -150% GP from Combat -6% Chance To Double Loot in Combat +15% Damage to Monsters in Dungeons
15	Waterfall Crossing	-100 Maximum Hitpoints Your Attacks now roll twice (Select highest chance) -10% Global Slayer Coins (except Item Sales)
Pillar	Pillar of Combat	+10% Ranged Evasion -0.2s Monster Respawn Timer +5% Flat Slayer Area Effect Negation +10% Melee Evasion +10% Magic Evasion +5% of Maximum Hit added to Minimum Hit +10 Flat HP Regen
Elite Pillar	Elite Pillar of Expertise	+8% Mastery XP for Melvor Realm only -3% Interval for all Non-Combat Skills +40% Global GP (except Item Sales) +8% Chance to Double Items Globally

Underwater City/Guide

Contents

Underwater City

Introduction

Equipment

Agility