Depth 4 Dungeons Guide

Depth 4 Dungeons are substantially more difficult than previous depths. Relatively little is known about how to tackle them. This page has some information that may help.

Overview
The suggested starting point for a depth 4 dungeon team, according to the game's developer, is Dungeon Level 220, Class Level 60, 150k Growth, and a mix of tier 3 and tier 4 equipment. Obviously this is not a firm requirement, nor is it sufficient for all cases. Having large Dojo dungeon buffs will also help.

Before attempting these dungeons, all of your team's equipment should be at minimum fully maxed tier 3 (SSS +20 with 20 enchantment and a level 10+ gem). A scattering of tier 4 gear will help. Due to the large amount of damage you may receive, a higher than average number of water gems is strongly advised for most pets.

Each depth 4 dungeon has 2 regular (preventable) traps, 1 unpreventable trap, and 2 events. The events are consistent across all dungeons. Passing the first one requires a key which matches the dungeon's element, and if passed, gives 1 crafting bar of the dungeon's element (e.g. Titanium Bar) and 30 god power, and increases the monster attack and health by 50%. Passing the second one requires all 6 team members to match the dungeon's element, and gives one tier 4 crafting material (e.g. Mythril), 5 growth in each stat to each pet in the party, 25% more experience (presumably in this room only), and increases monster attack and health by 50%.

The keys for the first event may be crafted by an Alchemist from the stones found in the matching element's Infinity Tower, or looted from the depth 4 boss.

Speaking of which: each depth 4 dungeon also has a boss room, which occurs as the 60th room. Reaching it requires that all NRDC have been completed, and needs a full 12-hour expedition. The boss room is significantly more challenging than regular depth 4 rooms.

Alchemists may also craft Nanotraps and Freezing Bombs. Nanotraps act against the Nanobot monsters in the depth 4 Scrapyard. Freezing Bombs reduce the speed of depth 4 monsters by 50%, but may not be used together with Nanotraps or keys.

When attempting a depth 4 dungeon for the first time, you will probably be unable to defeat the boss room, or any room that gains 50% monster stats from passing the events. Therefore, it's unwise to bring keys or to use a single-element team (for now), or to allow a team to remain in depth 4 for a full 60 rooms. You may need to bring Freezing Bombs or Nanotraps, depending on the strength of your team, and which dungeon you're attempting.

Next, we'll look at each dungeon.

Scrapyard
The unpreventable trap is a Railgun that shoots one random pet for 20k damage (more at increased difficulty levels) which ignores defense. A pet killed by the Railgun can't be revived in the same room where it was killed.

Due to the Railgun trap, pet Health is of utmost importance. It might be wise to use nothing but water gems here.

One of the monsters is a Nanobot which can replicate itself, unless prevented by Nanotraps. Nanotraps prevent the use of Freezing Bombs. There's also a monster which can Heal.

Water Temple
The unpreventable trap is a Lethal Poison which does increasing damage to every pet, every turn. It cannot be removed, except by completing the room, at which point it goes away by itself. Do not question the magic.

The Deep Sea Undine monster can inflict a Frozen Aura, which does additional damage per turn, and can also heal.

The key to this dungeon seems to be dealing enough damage to defeat the monsters (including surpassing the Deep Sea Undine's powerful healing) before the Lethal Poison reaches high enough damage to kill your team.

Volcano
The unpreventable trap is Oilburn, which deals 5% of max HP damage per turn, and reduces pets' Fire element by 100 * difficulty level.

This dungeon also features the Hell Rabbit, which can replicate itself, the regenerating Obsidian Giant, and the Infernal Salamander with a Healing Aura.

Mountain
The unpreventable trap is the Gravity Bomb, which reduces all pets' speed by 99%.

There is also a monster with Heal, in case the ridiculous amount of speed damage you'll take (compounded with only being able to act once per turn) wasn't enough.

Forest
The Forest is considered the easiest depth 4 dungeon, and is where most players will begin. In addition to being the easiest to survive, there's considerable incentive to succeed here, due to the potentially larger amounts of tier 2 and tier 3 wood that can be obtained. Special wood and magic wood are frequently needed for upgrading the Tavern or Dojo, or for crafting. A depth 4 difficulty 0 team with 2 Rogues can obtain slightly more special wood than a depth 3 difficulty 10 team with 3 Rogues. However, if you're currently farming D3-10 with more than 3 Rogues, you might wish to remain with that setup until you can handle more than just D4-0 without events or bosses.

Torches and Antidotes will prevent the regular traps here. The unpreventable trap is a Stungun which randomly stuns one pet per turn. This stun lasts for 3 actions.

The most significant monster in this dungeon is the Cosmic Gnome, which has 99,999 defense and 200 HP, and is immune to speed damage and defense deleveling by knives. Due to its insanely high defense, it will take 1 damage from almost any attack. The intended way to defeat this monster is with a Mage, dealing multiple attacks per action. There's also a bug which allows the Undine's special attack to deal more than 1 damage, but that may be fixed by the time you read this.

The fact that the Cosmic Gnome is the most significant monster is what makes this the easiest depth 4 dungeon. There are no summoners, no healers, no infinitely increasing poison damage, etc. There are monsters that can deal a lot of damage, but that's true everywhere. You simply need to survive the incoming damage, and deal enough damage of your own to win within the 50 turn limit.

Suggested team: 2 Defenders, 2 Rogues (or 1 Rogue + Hourglass), 1 Supporter (not Hourglass), 1 Mage.