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Now that you’re a Black Whistle, a lot more options open up. For one thing, you can now fast travel up to the 5th layer. What’s more, you can now fast travel from the 3rd and 4th Layers, too. It also costs less Health and Fullness to fast travel.

Now that you can fast travel from layer 4, you can also complete the Nanachi quests more quickly. What’s more, by fishing Hamashirama in the 5th Layer, you’ll no longer be stuck on the one requiring Hamashirama Meat. While you’re at it, you can take a quick trip to the Hidden Hot Spring to take some more relics up with you as you fast travel back up. The relics that Nanachi gives as rewards are usually those that you can find on the 5th layer. You’ll want to hold on to some, as you’ll need at least 5 of each, for a reason we’ll get into later.

Eventually, you’ll reach Nanachi’s Quest 10, in which Nanachi requests 3 Horizontal Layer Board, 5 Vertical Layer Board, and 5 Fox Bone. If you’ve been stocking up on relics, this shouldn’t be much problem. The reward for this one is Nanachi’s Helmet. There seems to be an oversight which allows you to go through the quests again and eventually get another Nanachi’s Helmet. So, unless this gets patched, you can get two.

I understand that a lot of fans are going to want to wear Nanachi’s Helmet on principle. For its weight, it offers some decent defense, and has three equip slots. However, it doesn’t have a light, and takes a lot of time and effort to get to. Personally, I prefer Hablog’s Hat at this point, but if you’ve gotten Nanachi’s Helmet, you’ve earned the right to wear it.

You have more options with your skill points. As usual, you can increase the weight capacity of your backpack so you can take more of that sweet loot back with you at a time. But I highly recommend Skinner, because that will double what you get from fallen primeval creatures, including what you fish up. This is huge.

Armor upgrades from 4-Star Items include the Bone set and the EX Warm set, and Relic Synthesis (Mid Class) grants High level relic weapons that will make some bosses much easier, and a new High relic armor set.

Guild HQ has more quests. Accept them all. Even if you don’t complete them, there’s nothing to lose in accepting them.

The Supply Shop has two new sets of armor: the Feather set and the Agile set. There’s also new weapons. The Caravan Fleet has a new set of armor as well, the EX Warm set. There are a couple new charms.

As for which armor I recommend, I’d say go for the Feather set. You don’t get to upgrade it until you get to White Whistle, but when you get there, you’ll be able to upgrade it to an armor set with an excellent combination of defensive ability to weight. Ambitious players may go for the Relic (High) set, but they’re an upgrade of an upgrade, which is a lot of trouble to go to for something that’ll just become obsolete when you reach the final rank.

Or, if you’re thinking ahead and you’re sure you want the best Relic armor when it becomes available, you could instead go for the Agile set. Once you reach White Whistle, the set can be upgraded again to the Agile (Black) set, then upgraded again to the Relic (Special) set. What you go for depends on whether you prefer high defense or more room in your bag.

But the most noteworthy of the Caravan items is the Type 4 Energy Rations, the best food item in the game. They’re light, and restore lots of Health, Fullness, and Energy. The main drawback is that they’re expensive, but it becomes easier to stock up on them with time.

At Laffi’s Shop, there’s a quest that has Hablog’s Hat as a reward. It’s actually not a bad hat, so if you already have the Feather or Agile hat, you might want to chest it until White Whistle, when you can upgrade them. You’re also rewarded with the Hamashirama Pot recipe, which Nanachi loves, and is not a bad recipe to go with until you have an easier time swinging Type 4 Energy Rations.

Laffi also starts selling Zutsugi Root, which you had no problem gathering, anyway. Yay.

Now, onward to adventure!

Near the entrance of the 4th Layer, in the Goblets of Giants, a sidequest opens up which initiates if you draw close to the purple exclamation point. There is a strong boss here, so if you’re not ready for it, you can avoid it by walking along the edge of the platform its on.

OPTIONAL BOSS: Orb Piercer
This battle works basically like any other Orb Piercer, in that it has only one attack, with a ridiculously distant area of effect. The emergency dodge is the only thing that seems effective to avoid it, but not always. Perhaps you have to dodge in a certain direction, like backwards. It does a lot of damage, and causes a special poison condition that does a lot of damage at a time. If you strike its face, you cause a moment of recoil. If you follow it up with one more well-timed strike, you might deny it an opportunity to attack, which is kind of cheesy, but still requires some timing.

The prize for winning is a Thousand-Men Wedge, but you’re expected to return it to Guild HQ, and when you bring it there, you lose it. But if you have it equipped to a piece of armor when you go to the Guild HQ, they won’t take it, but the quest will still count as completed, anyway. This Thousand-Men Wedge stacks with the one you get from Ozen, so if you have both equipped, you do HUGE damage with even weak weapons, but your Fullness drops much faster. So, don’t leave them equipped if you don’t plan on fighting for a while.

At some point, Jiruo will ask to go with you to Ozen at Seeker Camp. With fast travelling, this becomes trivial.

To initiate your Main quest, just climb down into the 5th Layer’s Sea of Corpses 1 to initiate a cutscene. Then your new Main quest becomes Head to Ido Front.

You’ll probably like the 5th Layer. The relics here are really valuable, the creatures here, while dangerous, are easy to avoid, and the map layout is easy to comprehend. What’s more, the Swarm Shockers (Blue) that spawn in when you spend a lot of time in one area aren’t aggressive, so you can take your time fishing if that’s what you’re up for.

There are certain spots in areas like Sandy Ice Area 1 which are large, round, and flat, and might start to crack with a little walking on them. If this happens, get off of them. If they break, Stingerheads will emerge, and if you’re right on the center when it breaks, it’s an immediate Expedition Failed.

In the northeast part of Hail Jail, near the pond, there is an optional boss that has a random chance of spawning with each dive.

OPTIONAL BOSS: Interference Device #5
There’s really not much to this boss. If you’re using the strongest Relic gun, you might defeat it pretty quickly, especially if you’re at a high level. This boss has a chance of respawning with each dive, which is great considering its potential rewards. Upon defeat, it will reward you with random relics. Most of them are relics that you could obtain from the other layers, but you have a small chance of obtaining more Thousand-Men Wedges this way. There is also a small chance of obtaining a Star Compass, which isn’t that great, but it’s the only way to obtain Star Compass in this game, which might matter to you if you’re a completionist. To save scum for the relic you want, first determine whether this boss appears on the current dive. If so, restart from an auto save, then use a mail balloon right before initiating this battle, for convenience.

Ido Front can be accessed by going from Sea of Corpses 1 to Sea of Corpses 2 to Eternal Garden to Hail Jail to Sandy Ice Area 1 to Ido Front. There, you can enter Ido Front Internal.

This is it; it’s time to confront the Sovereign of Dawn, Bondrewd the Novel. If you remember everything you’ve heard about him, you might think that Bondrewd is some kind of monster. As it turns out, he’s worse than you might have thought: He has a fetch quest for you.

Five each of Maze Twine, Double-Bell Ball, and Spiraling Heat Stone. If you’ve been doing the Nanachi quests, you’ll have a slight head-start. Each of these are relics that you can find in the 5th Layer. If you’re down to the last two and are getting frustrated looking for the last ones, you can resume from an autosave if a sparkling red ore near an autosave didn’t give a relic you wanted.

Once you have all the relics you need, you need to bring them all to Bondrewd in Ido Front Internal. They’re heavy, so you’ll want room for them. You’ll also want to be combat ready, because a fight begins once you return to Bondrewd, relics in hand.

BOSS: Bondrewd the Novel
If you have at least one Thousand Man Pin equipped, this battle will probably be too easy, and you could probably just finish it up by running up to Bondrewd and swinging away until he stops doing mean stuff. Otherwise, you’re going to want to have relic weapons and plenty of healing items. If you hate quicktime events, you’re going to want to finish him quickly, because one of Bondrewd’s attacks, Gangway, can hit you anywhere you’re standing, and can only be avoided by quicktime event. His melee attack is a swing from his tail, which has a decent range. He also has a ranged attack, Far Caress, which begins as a dark sphere surrounding your character, which then shrinks around them. You can avoid this with Emergency Dodge. Once you’ve done enough damage, a quicktime event initiates in which you must mash a button. Fail it, and the battle continues with Bondrewd gaining a little more HP. Otherwise, you’ve won.

Once Bondrewd is defeated, you’re rewarded with two items: Prushka’s Hat and a replica of Bondrewd’s whistle. The hat is probably lighter and provides less defense than what you might be wearing, and doesn’t have a light. It’s more of a trophy item than a practical equip. As for the whistle, it increases arm and leg injury resistance when equipped to a piece of armor. Not bad.

But it’s not over yet, because there’s one more battle. It’s up to you to prepare or face the final boss, head on. If you’re ready, proceed from Ido Front Internal to The Altar.

FINAL BOSS: Tiare
Tiare is your size, and he’ll run about, trying to draw close with his hatchet. He uses a combo attack similar to the way you can if you’ve been spending Skill points on your weapon. He can also unleash a burst of energy that radiates in all directions, with little warning. The plus side to this is that after the attack is complete, you get a huge opportunity to attack. Like with Bondrewd, once you’ve whittled his health down, a quicktime event initiates in which you have to mash a button. If you fail it, the battle resumes, with Tiare regaining a little bit of health. If you succeed, the battle is over, and you’ve won.

After the battle ends, you’ll obtain a Life-Reverberating Stone, but you’ll need to approach the pod to gain the benefits associated with becoming a White Whistle. Doing so will make the credits roll.

Once the credits roll, you’ll get to save the game, and can resume from this Clear Data on the surface as a White Whistle. You’ll also have a replica of Lyza’s White Whistle in your inventory. This can be equipped to a piece of armor to increase your critical hit rate.

Congratulations on becoming a White Whistle!

For those who might become adventurers, there is a choice: Death, or unfulfilled longing. Which one is more dreadful? For those who are adventurers, the choice is already made. What awaits those for whom even death is not a deterrent? That is decided by the adventurers.

To Part 8: White Whistle

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Back to Part 5: Moon Whistle (Part 1)

Making it to the 4th layer, you’ll still be a Moon Whistle, so shop inventory doesn’t seem to change, and you’ll have access to the same skill trees as before. You’ll be able to fast travel into the 4th layer, but you still won’t be able to fast travel out of the 3rd Layer, so when you begin your dive into the 4th Layer, be prepared for the return trip through the third. Also, just diving into the 4th Layer takes a lot out of you, so you’ll probably want to bring plenty of eggs just to offset the cost of the trip.

A Hunting Party side quest becomes available, and it’s pretty simple, as it only requires going to the 1st Layer. It’s a quick battle that ends with a simple quick-time event. Also, if you found the missing Moon Whistle that Marulk asked you to find in the 3rd Layer, and treated his injury, you can take his letter to Marulk and complete this quest. If not, don’t worry about it. You can beat the game without taking on this quest, anyhow.

Like most layers in this game, the 4th has an apex predator that you might be better off avoiding, if you can. In the 4th, that would be the Orb Piercer. This nasty critter has tons of health, and has a nasty attack that’s fast and has a long area of effect that can hit, even from a seemingly-safe distance. What’s more, they also inflict a special poison condition that takes away more HP at a time than red poison, and can only be healed with a special kind of antidote or by returning to the surface. Usually, avoiding these is not a problem, but there is a possible Orb Piercer spawn location on a route in a 4th layer questline, so it’s not a bad idea to bring along some extra Mail Balloons and trying to find an opportunity to sneak around it.

Before journeying into the 4th Layer, it’s recommended to bring plenty of Ropes, because shortly into it, you’ll initiate a questline which will require lots of ropes just to get around. You can find Rhombus Thorn Plants that can help offset the use of Ropes, however.

If you have any questions as to whether the events in this game are canon, this questline should answer them. As you enter the 4th Layer, you’ll encounter Riko, who wants a certain herb, and won’t allow you near her until you have it. It’s nearby in the Goblets of Giants. Bring it to her, and she’ll join you as you both search for Reg. This can last a while, and involves some fighting, so be sure you come prepared with lots of food and weapons.

Just for bringing the Spring Bringer herb to Riko, you’ll be gifted with Old Cave Raider Hat. It’s like Marulk’s hat, but with a bit more defense, but Marulk’s hat still provides more light.

The layout of the Goblets of Giants seems to sometimes change on subsequent visits, so don’t be surprised if you sometimes see a different layout.

That aside, you’ll find Dechuanga’s guide along the way, in the Giant Vine bridge. This concludes the 4th Layer Investigation, so continue with Riko. Hopefully, the game didn’t decide to spawn an Orb Piercer along the way. If so, use a Mail Balloon to make a place to resume from in case things go wrong as you try to get around it.

The journey takes you to Eternal Fortunes. Here, you’ll have a battle against a Kudara. After that, Riko will task you with finding 2 Hard Meat and 2 Eternal Fortunes. The Hard Meat is a drop from the Kudaras that are nearby. After you’re done, it’s back to the Goblets of Giants. The questline concludes with 2 battles against groups of Horncriers (Subspecies), which puts some wear on your weapons. But your prize for all this is the Scaled Umbrella, which doesn’t have much attack, but high durability. As far as I know, it’s the only one you get.

After your playdate with Riko, you’ll be near the entrance to the Goblets of Giants, so go ahead and make an autosave for yourself by using the entrance, if you want, just in case something goes wrong.

It’s possible to meet Nanachi in this game. The method is so obscure that many players aren’t even aware that meeting Nanachi is possible. To do it, you need to have no one in tow, so finish up the Riko questline. Then, you need to take a fall that normally does lethal damage. Taking a fall from anywhere where you’d normally use a rope may suffice, as there’d have to be a solid surface below.

Once the cutscene is over, you’ll have access to Nanachi’s Hideout, which can be accessed near the entrance to Goblets of Giants. There are many perks to having access to this place. Nanachi has quests which involves seeking out various items or ingredients, or Nanachi will request a prepared meal. You can give Nanachi just about any prepared meal, and the better the meal, the better Nanachi’s response. The reward for the meal is a high-grade relic, so give Nanachi the best you have to offer. Among the best items are Laffi’s Special Lunch and Hamashirama Hot Pot. Eventually, Nanachi will request Hamashirama Meat, which can only be obtained in the 5th Layer, so if you want to complete them all, they’ll have to go on the back burner.

From Nanachi’s Hideout, you can access Hidden Hot spring, where you can get some easy relics. You can also access Crystal Valley from here, so you’ll have a quick route through the 4th Layer.

Back on the surface, if you visit Guild HQ, you’ll find that Habolg has recommended you for Black Whistle. But there’s a condition: Go to a location in Deep Tree Remains by yourself and make it back alive. By now, you should know what that means: It’s another boss battle! You’re going to want to bring a lot of food for the trip there and the trip back. You’ll also want to be well armed. If you save two Relic Pickaxes for the battle, that’ll be plenty.

To get to the boss, fast travel to 4th Layer, then go from Goblets of Giants to Nanachi’s Hideout to Hidden Hot Spring to Crystal Valley to Giant Vine Bridge to Eternal Fortunes to Deep Tree Remains, where the boss can be found. This might sound like a long trip, but you’ll only be in most of these areas briefly. Head to the Main Quest marker on the map to initiate the battle. No prize for guessing the boss’s identity.

BOSS: Interference Device #4
As with the other ones, no need to scan it, this boss will be automatically added to your notebook. This guy is easy. He’s got a wave-motion cannon that he can sweep side-to-side, so be sure you’re not in front of him when he fires it off. He lets off a burst of flame right before firing it, so you only have a brief window to get some melee attacks in. But that’s it, that’s all the boss can do. His attacks do a lot of damage, but they’re predictable.

Once you defeat this boss, poke your head in the 5th Layer so you’ll have a fast travel point later on. Then, it’s time for a return trip. Returning through the 4th Layer the way you came is pretty easy. As for the 3rd Layer, here’s the video again for if you don’t already have the path memorized:
https://www.youtube.com/watch?v=5NUDVFpGvIg

The trip back is kind of long, but think of it as a victory lap. Enjoy your new Black Whistle!

To Part 7: Black Whistle

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Back to Part 4: Blue Whistle

As a Moon Whistle, you can now fast travel to the 3rd Layer. What’s more, it now uses less HP and fullness to fast travel. And if you so much as poke your head into the 4th Layer, you’ll be able to fast travel there, too. This part of the guide focuses mainly on your adventures as a Moon Whistle in the 3rd Layer. You won’t be able to fast travel out of the 3rd or 4th Layers until you are a Black Whistle, and that’s still a way’s off.

For one thing, you have another batch of quests at the Guild HQ which encompass the 3rd and 4th layers. Accept them all.

The supply shop carries a lot of new items, but are mainly either lighter or somehow more effective. You can actually get a lot of mileage out of the weaker weapons, but you might want to bring one or two different varieties of stronger weapons to switch between for stronger enemies. There’s also new armor sets: the Mesh set and the Bone set.

Laffi’s shop sells more indredients and items, the best of the new options probably being Adult Onigiri, as it’s light and gives more energy, which is great if you run low on energy while climbing. Other than that, you’re still well off relying heavily on Boiled Eggs and Crumbled Boiled Eggs. But make something unusual if it appeals to you, as you do have plenty of options available.

The Caravan Fleet has begun stocking the Warm armor set, as well as Special level charms. If scanning primordial creatures is your thing, a Telescope is now available, which can scan from longer distances, and can zoom.

Now for the Skill trees. Under Cave Raid, spring for Gatherer first. It’s more awesome than the description implies. You’ll get double what you forage from plants and other miscellaneous pickups. You’ll get enough to craft a rope from one Rhombus Thorn Plant, and each Broken Mail Balloon you find will give you enough materials to craft a Mail Balloon. You’ll also get to enhance the ability to wall climb, to the point that the walls in the earlier layers will become nearly trivial. Really, all skills in the Cave Raid tab are must-haves.

Under Craft, the 3-Star Items allows for upgrades to the Mesh set, while Relic Synthesis (Low Class) allows for crafting relic weapons, which are heavy and hit hard. Maybe you’ll want one, which can help big against powerful enemies such as Foreign Cave Raiders, in the event that they ambush you. It also allows you to craft Relic armor. Again, I don’t bother much with crafting ammo because you can just buy it and that seems like less trouble.

For Battle, prioritize upgrading Dodge and whatever weapons you prefer. If your melee weapon of choice is the pickax, focus on that, and if your range weapon of choice is the Bow, focus on that.

For recommended armor, I’d say go with the Mesh set and its upgrades, aside from Marulk’s Hat if you prefer it for its illumination. The Warm set upgrades are heavier, but provide not much more defense. Relic armor looks impressive, but doesn’t provide much defense relative to its weight and the resources that go into them, which include relics and the already-upgraded Cook set. Considering that it’ll become obsolete once you hit Black Whistle, the Relic armor set probably isn’t worth the trouble, and you’ll probably find yourself preferring the weight allotment of the Mesh set for longer dives.

Now be warned: The 3rd layer can be confusing for those who don’t know it well. And making matters worse is that there are many vertical locations, so the map isn’t going to help much in some cases. But it helps to have a route memorized, and if you can find that route, getting back to the second layer (and thus the surface) becomes much easier.

s gwilly on YouTube has an unlisted video in which he demonstrates a route from the room where you battle the Boss to the second layer, which requires 1 Rope to complete. Here is the URL to the video:
https://www.youtube.com/watch?v=5NUDVFpGvIg

If you can memorize that path, you’re going to be in great shape. And don’t worry, the 4th Layer is going to be much easier.

There is a quest that can be activated at Seeker Camp in which you search out herbs with Marulk. Because you can fast travel to the 3rd layer, you can easily access Seeker Camp from Heaven’s Waterfall by simply turning around at the entrance to the 3rd Layer. As part of this quest, you’ll have to fight an Ottobas. Run away to avoid its charge, and be cautious about attacking from the side, as it can get on its side and roll. It’s not much trouble if you have a Relic Pickax, and defeating it takes a quicktime event. It doesn’t provide much time window, so pay attention. This is a great opportunity to complete the quest from the guild to defeat an Ottobas. Once Marulk’s quest is cleared, Marulk will give you another optional quest concerning finding a cave raider lost in the 3rd Layer. There isn’t much need to worry about it.

But if you’re up for something to worry about, you’ll get an optional boss battle if you were to go to Ozen’s Room and talk to her.

OPTIONAL BOSS: Ozen the Immovable
You can make any number of attempts at this boss until you win, and if you lose, it’s not a Game Over. But don’t get the idea that this battle is easy, as the typical player won’t be ready for this, even with the optimal gear available at this point.

Ozen can speed towards you, then grab you with her arm. If this connects, she’ll throw you straight up, high enough to inflict the strains of ascending. You’ll take damage upon contact with the floor, and lose stomach contents. Sometimes, the strains don’t kick in. I’m not sure what affects this, but may have to do with the fact that this battle takes place on a slope, and running about on it might increase susceptibility to the strains when thrown. Ozen can also lift boulders, and what she does with them determines how she attacks. She can just throw the boulder, which is easy to avoid. But if she crushes it in her palm, she’ll fire a conical spray of debris, which can be avoided with an emergency dodge.

At this point, Ozen’s damage output is too high, and yours is too low. It’s probably a better idea to come back to this after you become a Black Whistle. But the rewards for completing this battle are great. For one thing, you get Ozen’s Umbrella, the best hat in the game, even if it’s a little heavy and doesn’t have a light. You also get a Thousand-Men Wedge, an item that pushes your Attack stat into the sky when equipped, making even your weakest weapons catastrophic. It may even make the rest of the game too easy. You also get a replica of Ozen’s whistle, which increases HP when equipped.

Whether you go for this battle now or later is your call, but you’re probably better off putting it off.

There are a few optional quests that start appearing at this point. One involves a boy in the classroom who lost his father’s keepsake, another is from Jiruo, concerning a relic in the second layer, and Laffi has a quest for delivering a letter to Seeker Camp. None of these concern going deep into Hell’s Crossing, so they should be simple enough.

Anyhow, this is about the time in which you may start running into Foreign Cave Raiders. They’re enemies that appear in groups, and have access to weapons such as pickaxes and guns. There are spawn points where they may randomly appear, but they won’t appear unless you’ve triggered them. Whether they appear at a spot is determined randomly each time you enter the Abyss. When defeated, they tend to leave some nice drops, such as sophisticated weapons and prepared meals. But if you’d rather not deal with them, then try to memorize where you bump into them, and try avoiding those spots.

When you get the quest for High Temp Ecology Study, it helps to know that there’s actually an alternative entrance to the 3rd Layer that leads directly to the Cold Heat Layer. When fast traveling to the 3rd Layer, go back through the entrance to Heaven’s Waterfall. If you climb down into the fault, you’ll find an entrance to another location on the 2nd Layer called Updraft Wasteland. You can access the 3rd Layer’s Cold Heat Layer from there. As dangerous as the place looks, avoiding the lava spouts is no problem, just keep an eye out for the boulders. It’ll take a couple ropes to get you to the quest point, but by this time, you should have a stock of about ten ropes in your standard kit without being told to bring them. At this point, their weight and the funds needed to buy them are becoming increasingly trivial, so be in the habit of having plenty on you and replenishing them between dives.

Once you enter the small room, you’ll be unable to leave until you defeat 6 Mountain Spinner (Ice). If you didn’t bring enough weapons to complete the task, you’ll be stuck. A Relic Pickax is recommended, here.

The 3rd Layer introduces a new vexation that thankfully only appears in The Great Fault, Trapped Pirate Ship, Quadruple Pit, and Rock Slide Hall, and only outside: the Madokajacks. These things make climbing in these areas a nightmare, unless one doesn’t spawn near you. Because of these, you don’t want to waste time climbing. They are hard to avoid, thanks to the fact that they have hit boxes that are too big for their frames. They do a lot of damage, and if you’re climbing, you’ll probably take lethal damage from the fall. You can try killing them, but they have a lot of health, and you’ll pretty much need ranged weapons. So, for the most part, you’re better off avoiding them unless there’s some trick to them that hasn’t been figured out.

Anyhow, onto the first Main quest of the 3rd Layer: Investigate the Third Layer. First, head to Quadruple Pit. You can reach here if you continue on from your High Temp Ecology Study quest. Just continue from the Cold Heat Layer to Glass Layer. Near the bottom of the room, you can climb to a narrow corridor that’s blocked by ice that’s destroyed by simply sounding your whistle. Remember the boy who lost his father’s keepsake? You’ve found it. Just avoid the Crimson Splitjaw and climb up to a room with an ice block in the middle. Sounding the whistle again will start a small cutscene that will reveal the way to Quadruple Pit. Just inside, you’ll find Detchuanga (indicated by the yellow whistle on your map). Continue the video above from 8:30 if you want to return to the surface from here. The journey is short, but complicated enough that a visual guide helps more than an explanation.

The next point point of interest for Third Layer Investigation is in Trapped Pirate Ship. Reaching it is mostly simple. Fast travel to third layer, but turn around back to the 2nd Layer. Remember how you could then go down from Heaven’s Waterfall to the Updraft Wasteland? There’s another entrance to the 3rd Layer if you keep going down from the entrance to Updraft Wasteland. This leads to The Great Fault. Oh the left, along the wall, you’ll find some caves. The furthest one over leads to Trapped Pirate Ship. Make a rope, and go down into the cave below to initiate a cutscene with a couple familiar characters.

The Main quest Third Layer Investigation and High Temp Ecology Study converge in the Freezing Hot Mines, which is accessed via Rock Slide Hall. To get there, you’ll need to climb down lots of walls where Madokajacks may appear. It takes some exploring the internals of Rock Slide hall, but you’ll be on the right track when you follow a long tunnel down.

Shortly after entering the Freezing Hot Mines, you’ll be unable to escape until you defeat 1 Mountain-spinner (Fire) and 3 Rock-lickers. After that, your ecology research and the request from Jiruo will be complete!

Your Third Layer investigation concludes with a boss battle, which initiates when you access the yellow whistle on the map.

BOSS: Interference Device #3
This one is airborne, and will fly about. It will occasionally stop, and make pillars of lava appear, which are indicated by red circles as warning. You can damage this boss by jumping and swinging your weapon, but sometimes you’ll be able to hit it from the ground without jumping, despite the appearance of distance. This one isn’t too hard, but don’t get hit, as the lava inflicts red poison. Red poison drains HP. As with the previous Interference Devices, it will be automatically added to your Notebook.

As your reward, you’ll gain access to the 4th layer, and your Main quest becomes Fourth Layer Investigation. Hooray for progress!

If you do enter the 4th Layer and travel a short distance, you’ll initiate a quest line that you’ll be unable to end until it’s completed, so unless you’re willing to commit to it right away, just poke your head in to make a fast travel point, then follow the route in the video above to quickly return to the surface.

To Part 6: Moon Whistle (Part 2)