First of all, Haven is an exploration and story rich game, so you may like to discover it all by yourself before reading a guide like this one.
You can obtain all achievements except one in a single playthrough, and you can launch an automatic save after finishing the game to get all remaining achievements, so take it easy and enjoy the game!
There are minor spoilers ahead, no big spoiler about the story, but nonetheless spoilers.

THIS GUIDE CONTAINS MINOR SPOILERS!!!
Be warned there are some (major) story spoilers in the comments.

This guide is not a walkthrough. It is more focused on achievements, optional bosses, collectibles and confidence.

This guide is based on my notes for an eventual second (and now third) playthrough, especially for the "confidence" chapter.
At some point I added details I found on forums (Steam and others) because I couldn't find all the solutions by myself, so not every information here is mine (ex: the Beruberu boss). But I personally verified by playing every information present in this guide.

However if some information in this guide is incomplete or incorrect, please comment bellow, and I will correct it.

Note: I am playing Haven solo with a PS4 controller.

You cannot save the game by yourself, it will save automatically when you change of area. Keep that in mind and don't quit the game before exiting your current area, or it may be very frustrating.
I read dev saying they are working on manual save.

Healing hug (idling while low life) can heal a great amount! In fact the character with the lower life will heal until his/her HP are the same than the other character.
So in fight you can always shield with the same character and full heal him/her after the fight. But shielding with a depleted shield is against the game mechanics, and your character will take more damages… (It's not RP and I like to play RP in this kind of game, so I didn't use this trick!).

You will unlock a map at some point of the game, so don’t worry!

Take care of Oink!

Try to give creamberry fondue to Birble.

In the settings you can enable an option allowing you to look around while gliding:
=> In Controls => Allow camera control while gliding.

There are a lot of post meal cutscenes, so don’t hesitate to take a meal in the Nest whenever it is possible! If you are playing RP and eating at least twice a day, don't worry about it!

In this game you will earn more XP with discussion between characters than by fighting. Meals help too.

Lovebirds
Hold each others' hands and never let go

The two characters are holding hands when you glide without turning too much. Just slide in straight line for about 10 seconds, without parting hands. It's very easy while solo playing, I don't know about co-op.


Flower Powered
Try on the flower boots

During the epilogue, it's not missable.


Hug therapy
Give a healing hug

While one or both character(s) low life (in yellow or red highlight), stop moving to trigger the idle animation, which will be the healing hug.


Head in the clouds
Become a bird perch

Idle in the grass were there are birds, Yu will sit and a bird will land on her head.


An eye for an eye
Take a spill each, back-to-back

Near the end of the game, you will learn how to make one character propel the other in order to catch animals like "flow squids". You need to make one character throw badly his other half, without catching anything. Do it a second time by reversing the positions and the achievement will pop. Revenge!


Life’s short, ride long
Land a double backflip

I just jumped gliding full speed from a cliff. It’s pretty easy, it’s a double flip only because both of them flip once!


Ain't no mountain high enough
Reach the heights

There is a thread of flow near the entrance north of Benadon, which leads to the mountain.


Over my dead body
Block attacks until exhaustion

Shield successively with the same character in a fight until his/her shield runs out. You can know that a shield is weak because it turns purple.


Last minute
Launch a max-power assistance

With a fallen character (let one character lose all HP), help him/her with the other, wait for the spin to circle two times, and release the button when the two light bars are blue. The help button is only available on a character when the other one is down, it's the bottom button, replacing the shield.


Perfect timing
Launch a max-power double-attack

While charging an attack both together (double attack), wait for the circle to spin until the two lights are on (until both bars are blue). It’s easy when surprising enemies before beginning the fight.


Strike!
Hit 5 critters in their weak spot, in one swoop

Wait for a fight against five or more enemies, and the first time the game will show you how to use a capsule, which will one-shot all enemies enemies at the same time. You'll need to use an omni-impact or an omni-blast capsule depending on the enemies.


Shake the rust off their feet
Pacify five critters in one swoop

Easy to get with the Strike! achievement, once the five enemies down, pacify them at once. Do it quickly before they raise again. To do so, use the capsule with one character while charging the pacify with the other, and it will run smoothly.


Unstoppable
Finish the game with 3 KO or less.

Having one character down in a fight doesn't count as a KO even if you don't help him/her before pacifying the last enemy. If you undergo a real KO (both characters having lost all their HP), you can still exit to main menu and reload, the KO will not be counted, but you will lose a little bit of your progress.

There is just bellow an entire chapter about strategy to beat these bosses. For a minimum spoiler in this section, here you will only find the way to find them.


Thar she blows
Beat the Beruberu

You just have to spend one day (in game time, so around 24 minutes real time) without coming back to the nest for this creature to appear. First the floor will shake and the sky will become red, and a few minutes later the whale will suddenly appears, chasing you. I just waited idling on Chogeme, but I think any islet do.


Back to rust
Beat the Lorudo

You can find Lorudo on several islets such as on Lonarow, Wakiri or Loname.


My little pony
Beat the Heliga

Like Lorudo, you can find the Heliga on several islets. I found it on Nekame.


Balding bloot!
Watch helplessly as the Nest falls


Like new!
Finish repairing the Nest


Second thoughts
Choose not to sever the flow bridge


Don't look back
Choose to sever the flow bridge


The best ones, often goes with a nice cutscene!


Mooning the moon
Midnight skinny dip

Wait until night or come at night on the beach in Chogeko islet. Interact with the sunbath option on the sand, a dialog comes, then a cutscene.


Can't get wetter...
Getting handsy under the waterfalls

You'll find two waterfalls on Nekarow. Interact with both of them once, you'll get a cutscene for each one.


Pearls before Birble
Lure in Birble with creamberry fondue

Give some creamery fondue to Birble, climb on it and you will go to a new unknown islet.


In my shoes
Taste the hygrocybe rubescens

Take care of Oink!
Pat Oink from time to time (each time that trigger a cutscene counts), and eventually you’ll get some mushrooms. The characters will eventually try the mushrooms after a meal in the Nest, just wait and enjoy the cutscene.


Heartstrings
Play a guitar ditty

You need to find a shell on the beach in Chogeko (plunge in the water from the top pic, then explore the cave), and then eventually (not necessarily at the first try) Kay will make a guitar from the shell (cutscene after a meal in the Nest), and at one of your next campfire night, after eating Yu will play (it's the Space Caress track, and it's lovely!).


Strip-a-bobble
Lose a game of strip-a-bobble

It’s a random dialog after a (non-appledew based I think) meal. Just have lunch in the Nest and this cutscene will come eventually!


A love supreme
Reach the maximum relationship level

You will get this easily while playing. But if you want to speed it up, eating and talking are the best way to tie bounds between characters.


Self-sustainability
Fill the vegetable patch

Catch three seeds for each kind of plant (there are six kind of plant so a total of 18 seeds is needed) and go back to the Nest. Yu and Kay have a little game about gathering these seeds. Keep changing characters while gathering the missing seeds and you should finish it easily near the mid/end game.
I'm not sure that the special seeds (Firefluke seed and Catilla spirata scale) are needed in order to get this achievement.


À la carte
Taste every dish

You need to eat every dishes in the game (I'm not sure about the campfire's one, I personally got this achievement after a meal at a campfire). I think you need to discover every meal stats (no "???" remaining), so to my mind you have to eat every meal from the Nest (15) and from a campfire (6).


Spring cleaning
Clean up the rust on every fragment

On your map in the menu, with the cursor on an islet, you can see a panel on the right of your screen. It contains information, such as if there are still rust on this islet. It will be written All clear! otherwise. For islets where the rust respawn, for instance Wakiri, I think you only need to clear them once.
Apparently you don't need to have Wakiri cleaned up at all (to be confirmed).

Since the release of version 1.0.165 of the game, a save is automatically created before the ending, so you can launch it and get the other ending.

Information here are not all mine, I just gathered some useful data from forums and Steam Discussions.

Before attacking a boss, make sure to have some balms crafted. I've found having tonic capsules to be very useful. It is preferable to have some omni-impact and omni-blast capsules too, and to be max level.

Remember to block at any time, and you should be fine.

Achievement: Thar she blows

I read that some people can't use a campfire between when you spawn Beruberu and when you fight him, but I personally was able to do it, so I didn't fight him hungry.

I used for this boss a strategy from N7 Reyes found on a forum (TrueAchievements).

This boss is only vulnerable to duo attacks, don't try solo attacks on Beruberu.

The first phase is easy, just use duo blast then duo impact.

For the second phase, the boss the have either a red or a green aura. When Beruberu have a red aura, it will be weak to duo blast. When the aura becomes green, it will be weak to duo impact.

And finally the third phase is when it starts charging up its laser attack. you have plenty of time to prepare your shields and wait for it to attack. It's not worth trying to squeeze in one more hit, trust me. I believe it attacks in two successions so wait for that second attack. After the second laser it should be stunned and you’re good to continue the combo.

Now for actually getting some damage on this unit you’re going to want to hit it with a blast or impact capsule while it’s stunned. Charging up duo attacks takes too long in comparison to having one/both of you using a capsule attack. That or use a tonic capsule at the beginning of the fight.

Good luck and remember to block!

Achievement: Back to rust

In this fight I ignored the two little mobs, because the boss will respawn them, so I just shielded their attacks.

Shield all attacks alternatively with Yu and Kay.
The other one will throw three blast (distant) attacks in order to make its eye glow red, then deliver a duo impact attack to deal huge damages, and repeat.

Achievement: My little pony

Kill the two other mobs, more importantly the left one, which is a healer.
The boss fight itself is a classic fight, without difficulty.
He will kindly heal you after the fight.

This is my favourite part of this guide, and the reason why I made this guide, but certainly it's the less useful part too. The visual novel side of this game with 2D sprites and story rich dialogs are for sure the main reason why I love Haven.

The goal of this chapter is to max out confidence of both characters by dialog choices.
I'm not sure about the usefulness of doing this, and the impact of an high confidence on the story.

Confidence seems to be a stat not shared between Yu and Kay, and will impact your ending, but will not change your ending. The character with the least confidence will be severely injured protecting his other half.

I suggest you to simply choose the answer you think the character will respond regarding the situation (and so don't read this chapter).

Not all choices up one character's confidence. Choices lead always to the same conclusion, whatever you choose. You will just have some little (spicy) information about Yu and Kay.

I probably missed some dialog choices, so feel free to comment and I will add them.

There are a lot of spoilers in this chapter (but none on the endings) be warned!



Accident - Earthquake
To be added!

Is there anything from the Apiary that you are gonna miss ?
(After repairing the gyro, resting near the little lake near the Nest)
Yu: … No.

After fixing the propeller of the Nest
Kay: If you would please follow me into the bedroom.

Vid-chat!
Yu: Never been readier.
Yu: What if we don't want it to be back to normal?
Kay: Everyone would be happier.
Yu: Absolutely.
Kay: What about your mess?

Yu alone at Nakako's campfire
Yu: This is all her fault!

Crafting the Hyper Gloves
Yu: Do you have an appointment somewhere?

Just finishing repairing the ship
Kay: How do you feel about eating out here?
Come on, time's a-wasting!

Taking off the ship
Kay: Perfect!

Finding our first seed !
Yu: You can count on me !

Could it be the archives are… lying ?
(On the same island as the first “boss”.)
Yu: Erm… Of course they could be!

Discovering dwellings on Tsupiri
Ken: I would like to think it’s good news.

First time riding not-Burble
Kay: Into the unknown!

First encounter with the Apiary's hornets
Kay: We can get them!

In a house on Chogedon
No but look: there’s a tunnel here!

Discovering the beach on Chogeko
Yu: Let’s do it!
Kay: Ok…. Let’s try again together.

Exiting the beach on Chogeko
Kay: We would have found a way…

Skinny dipping
Yu: For sure.

In a house on Nekako
Kay: We're gonna need to burn these suits...

Discovering dead hornets on Guyapa
Yu: Cool.

Discovering the crashed ship on Nekatai
Yu: Wanna sever this flow bridge?

First cooked meal in the game
Kay: We are going to need to, at some point.

Fist time eating harmony bun
Kay: Wanna bet?

Fist time eating creamberry fondue
Kay: You ain’t seen nothing yet!

Lazing around in bed after lunch
(Dialog in bed)
Kay: Alright! Let’s get to it!

Wouldn’t you want to meet your mate?
(Dialog on the sofa)
Kay: Then no.

First time playing Alpha Zooloolum
Yu: Can’t we just learn them while playing?

Second time playing Alpha Zooloolum
Yu: I’ll do the Governor thing.

Reading the Illustrated Erotica Handbook
(Dialog in bed)
Yu: Ok.

Do you have any idea what time it is ?
Kay: Not really.

Your feet are freezing!
Yu: Ok. Go ahead.

Yu’s first shooting star (2nd try)
Yu: Ok! What do I do?

After opening the door
Kay: It would be pretty reassuring in a way...

Our first level up ! Level Up 1 => 2
Yu: It wouldn’t have change a thing.

Level Up 2 => 3
Kay: Because you asked me to!
Kay: Honestly? No.

Level Up 3 => 4
Yu: We press on! Press on!
Yu: I unbutton his pants.

Level Up 4 => 5
Nothing ?

Level Up 5 => 6
Yu: I like it here…
Kay: Not on Truth..

Level Up 6 => Max
Nothing ?

Having every collectible is not required for an achievement, but each collectible found unlocks some dialog (often post meal) and sometimes it's an item to add in the nest.

Mandatory ones, you'll get them all through the story.


Yu's Ribbon
Already in the inventory at the beginning of the game.



Kay's Medal
Already in the inventory at the beginning of the game.



Radar
Early game, obtained on Guyatai.



Antigrav sticks
Early game, obtained on Guyatai.



Hyper-rust
On Nekatai and Lonako, obtained after beating Lorudo and after enough interactions with Oink. Only two are required to finish the story.

Getting one of each is mandatory to finish the story.


Extender nozzle
Found on Atokko.



Fertilizator
Found on Tsupiko.



Left wing
End game, found on Wakime.



Right wing
Found on Kinoko (and Lonadon?).



Gyro-stabilizer
Found on Chogeko (and Katerow?).



Cylinder
Found on Benadon (and Loname?).



Waduz turbine
Found on Benahi (and Nekatai and Notame?).



Engine-hood
Found on Bename (and Nekari?).



Hypo-propellers
Found on Katehi (and Wakitai?).

Firefluke seed.
Found on Tsupiko.



Catilla spirata scale
Birble stations, not really a collectible.


The more interesting ones, they will unlock additional dialog.


Bunch of cables
Found on Katerow.



Illustrated Erotica Handbook
Found on Lonadon.



Massage oil
Obtained after beating Beruberu.



Muffin & Cupcake
Found on Benadon.



Bodigado's antlers
Found on Guyapa.



Heliga Faether
Obtained after beating Heliga.



Fitness Accessories
Found on Tsupiri.



Alpha Zooloolum
Found on Guyarow.



Teapot
Found on Sosadon.



Singing Daiko
Found on Lonako.



"Glowing Slugs"
Found on Benahi.



Hygrocybe rubescens
Gathered on Oink after enough interactions.



Acrobots Poster
Found on Nekame.



Sneddy
Found on Loname.



Souvenir Conch
Related to the Heartstrings achievement, found on the beach in Chogeko, then transformed.

Veggies/fruits stack by five.
Healing plants stack by three.


Every component here stack by five.


Every component here stack by three.


You have to choose two stack of different components from three.
Don't worry there is much more rust in the game than the one needed to repair the Nest.

Balm (to cure)
Crude rust stacks by 9.
Fine rust stacks by 4.
Shiny rust stacks by 1.

Omni-impact (damage)
Crude rust stacks by 4.
Fine rust stacks by 2.
Shiny rust stacks by 1.

Omni-blast (damage)
Crude rust stacks by 4.
Fine rust stacks by 2.
Shiny rust stacks by 1.

Tonic (speed)
Crude rust stacks by 9.
Fine rust stacks by 4.
Shiny rust stacks by 1.

Little bonus if you enjoyed playing Haven:

Devs shared some wallpapers and loading screens for download here[www.dropbox.com].

If some information in this guide are incomplete or incorrect, please comment bellow, and I will correct it.

Huge thanks to The Game Bakers for this game, I just love it. I waited for it for more than one year, and at the end it was exactly what I was waiting for!

I loved the story, I loved the ending, I loved the gameplay (like always charging attacks, combines attacks, shielding the other, cooperation, etc...), I loved wandering through all these islets. I loved the jokes about the Turnovers à la Kay, Yu playing guitar on the menu after having the camping guitar cutscene, all these details are awesome, and there are so many!

Thank you all the devs who are really active on forums!



Excuse me for some of my sentences which are not grammatically correct, english is not my mother tongue.

Thank you people for helping me polish this guide:

• jtron365
  
• Hurensohn
  
• pepesito1

Edit log:

• (2020/12/07) Guide release.
  
• (2020/12/23) Removing some section of the guide about creating backup save before ending, not needed anymore after the release of version 1.0.165 of the game.
  
• (2021/01/02) Adding link to wallpaper pack.
  
• (2021/02/12) Adding the collectable chapter.
  
• (2023/04/12) Updating wallpaper pack link.
  
• (2023/04/14) Updating craft pricing.

This guide has not been updated since the version 1.0.198 of the game.