• [03/2024] Since the game is new and there are still some achievements that no one has collected at the time of writing, I will attempt to unlock and explain them here!
  
  
• [08/2024] 4.0 UPDATE: I completed this guide a few months ago, and the game just got a major update with new achievements! I will try my best to add them ASAP; please let me know if some explanations below are outdated.
  
  
• [09/2024] The guide is up to date again!!

I've organized the achievements into categories, each representing a type of unlockable, which are as follows :

• 2 Game mode
  
• 9 Window themes
  
• 8 Backgrounds
  
• 6 Characters
  
• 3 Custom Cursors
  
• 3 Music tracks
  
• 3 Characters skin
  
• 1 Backing texture
  
• 2 Others

In the 'Others' category, you will find the only two achievements that do not unlock something in the game.

Note : you can check your progress on any given achievement in the 'unlocks' section in the game menu.

Timed run
survive for 20 minutes

As the title suggests, you will have to survive for 20 minutes in endless mode. For every timed achievement like this one, I recommend enabling the 'in-game timer' in options → gameplay.
My advice for this achievement is to use a character you are comfortable with, opt for the Multishot, and always keep a 'heal 20' available in the shop. Use it when your health is low.
Good luck :)



game mode: challenge run
unlock every character

To unlock this gamemode, you'll need to unlock all 7 characters in the game :

1. (Epsilon)
   
2. Bastion
   
3. Zephyr
   
4. Nyx
   
5. Mebo
   
6. :)
   
7. Blip

To unlock any of them, please refer to the 'Characters' portion of this guide.
Good luck!

Windows 3.1
get lv. 4 detach

If you want this achievement, you will need the character ':)'.

If you wonder how you can unlock him, check the 'characters' part of this guide in the index on your right.
Once you have it, start an endless game with him. 'Detach' is his special perk. To upgrade it up to level 4, you will need to defeat 10 bosses (1+2+3+4 = 10), and use these 10 stars buy the 4 upgrades :















Windows 98
kill 98 bosses

You shouldn't worry too much about this one. If you are aiming for 100% completion, you will unlock it before you know it. The fastest way to kill bosses is to have a strong build 20+ minutes into endless mode when multiple bosses spawn simultaneously.



Windows XP
manifest 50 items

If you are not familiar with the 'manifest' feature of the game, it is located on the 'perk' side of the shop. When you click on the 'manifest' button, you will be able to buy regular 'coins-items' but with stars instead :













All you have to do is to use this feature 50 times.
Note : The fastest way to get this achievement is to build a strong character and aim for the 30minute mark in endless mode, where bosses spawn 3 by 3. You will receive a lot of stars and will quickly be able to buy every 1-star upgrade. There are 30 of them, which will get you more than half of the achievement :



















Mac classic
block 200 bullets


To block bullets, you will need to purchase a shield. When you upgrade 'Drain' to level 3, it will grow a small blue shield in the middle of the damage area. This upgrade will cost you 6 stars (1+2+3) to buy. Once you have it, position it strategically to block bullets, such as the red ones fired by the 'Spiker' boss.

I actually obtained this achievement by accident while AFK on the 'Game Over' screen while writing this guide. Since the game is undergoing numerous fixes, it may be patched soon. Otherwise, use the 'Game Over' screen at your advantage !



If you have already unlocked Zephyr, you can also use his main attack to block the bullets. It might be easier than buying a level 3 Drain. So, if you want to know how to unlock Zephyr instead, go check the 'characters' section of this guide !






Macos 10
kill 2 bosses at once during halt

There are several ways of obtaining this achievement :

1. 'Halt' is the special perk of the character 'Nyx' (if you haven't unlocked him yet, you can check the character part of the guide), but you can also buy it in the shop with any character. The easiest way of doing it is to keep 2 bosses at low HP close together and buy the upgrade from the shop to kill them both.
   
2. If you own 'Nyx', you can just start a game in endless, kill Spiker, and buy 'halt' in the perk with the star. Then, you will keep only one node of 'Wyrm' alive, wait for 'Slimest' to spawn, kill every part of him except one of the smallest slime. Then bring them together and kill both of them in the few seconds after using the perk.
   
3. If you feel like you need more time, you could try to get this achievement along with 'Nyx skin: Hector', which requires you to get lv. 4 halt. You can check it out further in this guide if you want, although it might be a little more of an advanced strategy to go for.

Feel free to choose whatever fits you the most !



Macos 11
kill wyrm without causing a split




Wyrm is the second boss of the game and will spawn around 4 minutes into an endless run. As depicted on the left, it's a worm-shaped boss that will split if you destroy a middle part of its body. Therefore, you will need to carefully take down either its tail or its head until you defeat it completely. I recommend using a character that deals high damage, such as 'Bastion', and avoiding 'piercing' upgrades (but you can do it with every character in the game).






Cute
survive for 2 minutes without shooting the window as bastion

This one is self-explanatory : once you've unlocked the character 'Bastion', you have to survive for 2 minutes without shooting at the window. If you're wondering how to unlock 'Bastion', check out the 'Character' section in the index on the right.
If you're struggling, try staying in the middle of the screen, shoot only when you're sure to hit an enemy, and focus on upgrading 'speed', 'splash damage', and keep a 'heal 20' available if you need it.



Vaporwave
reach the end of timed mode as :)

To unlock this achievement, you will need to have previously unlocked both 'timed mode' and ':)'.

• To unlock 'timed mode', you need to survive at least 20 minutes in 'endless'.
  
• To unlock the character ':)', you need to beat the secret boss of the game.

If you need more details, check out the 'Game Mode' or 'Character' section of this guide.
If you have both of them and you are struggling with ':)', I recommend focusing on buying 'multi-shots', 'fire rate', and 'wall punch'. Once you have a star, purchase the 'detach' perk, and the bosses should become easier : use detach to attack the boss while being wherever you want on the screen.



window theme: shard
survive for 8 minutes in challenge mode

To get this achievement, you'll first need to unlock the Challenge mode' game mode. If you don't have it already, you can have a look at the 'Game mode' section of this guide (at the top).

The game mode is pretty fun:

• It gives you a random character to play with, random upgrades, no shop to buy new ones, and launches you at a random point in the game.
  
• All you have to do is survive 8 minutes from the moment you're dropped in. If the starting time is 4 minutes 30, you need to survive until 12m30.
  
• Keep in mind that, even without heal upgrades in the shop, you can still regain HP by killing a boss and collecting his loot.
  
• Knowing that this gamemode is unlocked pretty late in the game, it will probably only require a few tries for you to get the achievement. And if you're really struggling, you'll just need to play the gamemode until you're lucky with the RNG.

Have Fun!

Cells
buy 100 shop items

If you've already played a few games, you probably have unlocked this achievement. You will unlock it by purchasing 100 items from the shop.



Transparent
kill every boss

Bosses are stronger enemies that have their own window. They will spawn periodically and in the same order every run. wiki[windowkill.fandom.com]
There is a secret boss in the game, but it isnt required for the achievement.
The bosses 5 you will need to fight are :

1. Spiker (endless ≈2min)
   
2. Wyrm (endless ≈4-5min)
   
3. Slimest (endless ≈6-7min)
   
4. Smiley (endless ≈8-9min)
   
5. Orb Array (has a random chance to spawn after Smiley, endless >10min)
   
6. Infection (Miasma) (has a random chance to spawn an infected triangle)

Note : Orb Array is quite rare and has a low chance of spawning. You could spend 30 minutes in an endless run and not encounter it. Some players have reported better luck in 'timed mode', so you may want to give it a try there !
4.0 Update : Miasma has been added to the game, and is most likely considered as a boss. Therefore you should defeat it too in order to get this achievement. Unfortunately I have no way of checking if this is true or not because I got the achievement before the update. Feel free to contact me if you know for sure.



Grid
get 40,000 coins in one run

I got this achievement on a 20-minutes run with level 7 Wealth : buying the Wealth upgrade early in the game is key. You will have plenty of coins to upgrade what you need to survive !



Ripple
collect a 1000+ value coin

To create the 1000+ value coin, you will have to use the small pink enemy to your advantage : it can eat coins and will grow larger and larger until you kill it :
1.‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ 2.‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ 3. ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎‎‎ ‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ 4.










Having 'Wealth' upgrades can help in accumulating coins. Additionally, I advise you to avoid 'piercing' upgrades when using 'epsilon' since you do not want to accidentally kill the enemy. If it becomes stationary, use the window border to push it into the coins.
Note : The big coin shown in the fourth picture is worth 2100 coins, so you don't need to collect one that big.






You should also note that if you don't want to go through the process I just described, you can also survive for about 30 minutes. That way, you won't need to worry about feeding monsters; there will be plenty of big coins without you actually doing something (assuming you bought some 'wealth' upgrades during the game).









Soup
obliterate a star






This achievement can be unlocked in any game mode and with any character. The only thing you have to look for is the 'obliterate' upgrade in the shop. Once you see it during a game, do not buy it; instead, lock it. Gather enough coins to buy it, then defeat a boss without taking its star. Once the star is on the screen, you can buy the 'obliterate' upgrade, as shown in the picture on the left.








Stars
hold 8 stars at once

Basically you will need to kill at least 8 bosses without using their stars. Depending on the character you're playing, I recommend using the first star on either a character upgrade or Drain. This will make it easier to survive against the next 8 bosses.



background: vortex
collect 200 coins in a run as mebo without using any movement input

To try and get this achievement, you'll need to have already unlocked the character Mebo.
If you haven't already, you can check the 'Character' section of the guide.
If you have played with Mebo before, you probably noticed that he gets pushed back for every attack he shoots. The goal for this achievement is to make good use of this feature, leaving your keyboard behind and moving only by shooting in the other direction.
Here are some tips:

• You can spend the coins you collected; the goal is not to have 200 coins in your inventory but to collect 200 in total!
  
• Take advantage of this and try to buy a 'wealth' upgrade or use them to heal yourself!
  
• If you're struggling, you should focus on dodging the bullets more than you should focus on collecting coins.

background: infinity
kill ??? as every character

This achievement is pretty self-explanatory once you know how to defeat the secret boss'???'.
If you don't know or want advice on how to summon and kill him, you can check the 'Character' section of this guide, into the ':)' part.
If you're unsure which characters remain for you to get the achievements, you should check in the 'unlocks' part of the game menu:










----- Bonus -----
Secret Backgrounds:
If you want to download some great backgrounds for the game, there is a secret link waiting for you all the way down at the end of the credits.
--------------------

Bastion
kill 10 spikers


The spiker is the first boss in the game, it looks like this :

It will spawn in about 2 minutes into an endless game. An easy way of claiming this achievement is to successfully defeat him at the beginning of 10 games. However, if you face it again, you can use the 'drain' to kill him easily, since he does not move.




Zephyr
have 50 health

There are 2 steps for getting this achievement :

• Buy 'max health' upgrades until you reach n/50hp or higher
  
• Heal until you get to 50/n hp or higher

Note : You will not unlock the achievement if your current health is under 50 HP, even if your maximum health is higher than 50.



Nyx
get lv. 8 multishot


Multishot is great, but it's also expensive. To afford a level 8 Multishot,
I recommend also purchasing the 'Wealth' upgrade along the way :
I managed to acquire it in the same run I achieved the 'collect 40,000 coins' achievement !
Don't forget to restock if there is nothing interesting available in the shop
(you can 'lock' an item to save it from the restock with right click).


Have fun being overpowered !



character: mebo
kill miasma as nyx

To get this achivement, you'll first need to unlock the character 'Nyx'. If you want to know how to unlock him, feel free to check the 'Chracaters' section of this guide.
Miasma is a new ennemy that have been introduced in the 4.0 update of the game.













This boss is a bit special because it can spawn at any time during the game. It will take the appearance of a small infected triangle (1st pic), which, when defeated, will start propagating an infection and summon Miasma (2nd pic).
If any other boss spawns before Miasma is killed, they will be infected and become more dangerous.



:)
kill ???

':)' also referred to as '???' is a secret boss. It's quite complex to summon, but I've broken it down into 5 steps for you :

• Step 1 :
  
  
  
  The first step is to collect at least 3 stars to buy each of the 3 perks at least once.
  You will need :
  - peer
  - drain
  - your character's special ability
  (Buy them whenever you want, in any order)
  
  
  
  
  
  
• Step 2 :
  You need to find where the 'drain' window should go. There is a specific place where it belongs, with strips that will complete the one on your drain to make a full red square. Fortunately, there is a hint : small marks indicate where the secret spot is located. Follow them and place the window correctly. Once done, there will be an exclamation mark in the name of the window as shown in the right picture.
  
  
  
• Step 3 :
  
  Here we need to do the same as Step 2 but with the 'peer' window: this time you can find the secret location by moving the window in the same direction the eye is looking. Once both windows are placed correctly, there will be 8 strips all around the eye, which will start to glow when you stand inside.
  
  
  
• Step 4 :
  
  
  
  
  Stand inside the glowing eye and use your character's special perk.
  If you have done everything correctly, a '?' window should appear.
  Click on it to activate.
  
  
  
  
  
  
  
• Step 5 :
  All your upgrades will be reset (I think?), and regardless of your character, you will have a new weapon. The only thing you will keep is your character's special perk.
  To finally face the secret boss, you will need to destroy the window by charging your attack until it starts to blink, and shoot at a border. Now you can escape !
  
  
• Step 6 :

Now, you have to kill him by smashing the window into his face. You can launch it with your weapon.
If you are struggling too much to kill him, I recommend reading my advice from the secret 'friend' achievement (you can find it in the 'Others' part of this guide).



Blip
Secret achievement

This is the biggest secret of the game, it contains multiple layers of enigmas and riddles to solve. If you want to try and solve it on your own : close the guide and go ahead !
Note that I will describe the whole process, but you can skip both step 5 & 6 (I put [SKIPPABLE] in front of them so you don't forget).
Here is the explanation :

1. First you will need to unlock the character ':)'. If you don't have him, check the 'characters' part of this guide.
   
   
2. Then you will need to summon the secret boss again, but with the ':)' character :
   
   But do not break free too fast ! Look up the next step before.
   
   
3. Once you have your new weapon, you need to wait for your perk to fully charged again (the yellow bar at the bottom of the main screen). When your 'detach' perk is ready to use, charge a big attack, activate the perk and break free :
   
   You should see the window 'player' appearing around you.
   
   
4. Now, you don't need to fight, you just have to follow the yellow light in the background to find a text file and collect it by touching it. You can attempt to defeat the boss without taking damage to get the secret achievement 'friend', but if you get hit, you can return to the menu.
   
   
   
   
   
   
   
   
   
   
   
   
   
   
5. [SKIPPABLE] Back to the menu, you should see a new window labeled 'Feed me'. Create an empty '.txt' file (the name does not matter) and drag it into the the hungry window.
   
   
   
6. [SKIPPABLE] The '.txt' filed is now filled with a riddle (as shown below). It means that you need to feed an image to a level 4 'peer', which is an eye.
   
   
   
   
   
   
   
   
   Just as the '.txt', the image will transform into another one.
   
   
7. If you have done step 5 & 6, you have the secret image, otherwise you can download it here[files.catbox.moe], or look at it here :
   
   
   
8. Now all you have to do is to put the image as your computer's background, and rearrange the correct windows to the correct size, and place them at the correct position, and the 'title' window should light up (can be done with 'fake windows' option enable):
   
   
   
9. Finally, click on the glowing title window, and the blip window will appear ! Then you need to select it and start a game to get the achievement!

Rainbow
survive for 4 minutes without collecting a coin

You can enable the 'in-game timer' in options → gameplay.
The easiest method I found to achieve this was to avoid shooting at the ennemy, but aim for the border instead. It will be fairly easy to avoid the triangles for the first 2 minutes, then the 1st boss will appear and you will have to carefully dodge everything. If you kill something by accident, avoid collecting the coins.

Edit: As @GordeyW mentionned, Zephyr is a good pick, because he can move boundaries without attacking and accidentally picking up money.



Flame Sword
kill an orb array as zephyr

If you wonder how to unlock the character 'zephyr', you can have a look at the 'characters' section of this guide.
If you have him, here is a reminder :
Orb Array has a random chance to spawn after Smiley in endless (so over 10min).
He is quite rare and has a low chance of spawning. You could spend 30 minutes in an endless run and not encounter it. Some players have reported better luck in 'timed mode', so you may want to give it a try there !

Zephyr against Orb Array, Timed mode : 8 minutes left

v4.0 update :
If you've unlocked the 'challenge run' game mode, after completing the daily challenge, you can choose to start a seeded game :


@3R0 in the comment found a seed that happen to start as Zephyr and and orb array as the first boss. This makes getting flame sword much easier!
The seed is : "snlflnxd"



custom cursor: infected
kill an infected orb array

This achievement is quite hard to achieve, mainly because it mostly remains on luck.
To get it, you need to wait until the 2 rarest bosses in the game spawn.
This will take some time, so I advise you to start an endless game with a character you're comfortable playing with and then wait for an infected triangle to spawn.
The infection is not that rare, but it happens randomly. If you feel lucky (that an orb array may spawn soon), then you can try to hold the infection alive; otherwise, you can kill it and wait for an orb array to spawn.
This is what I did. I killed the first infection around 9 minutes in. I waited until the timer showed 22 minutes and an orb array spawned. At this point, I killed every part of his body except for 1, and then I waited for an infection to spawn again, cautiously avoiding killing the last piece of the orb array.
















As you can see, the infection finally spawned on the left, 26 minutes into the game.




Once both of them are on screen,
kill the infected triangle as soon as possible
and wait for the infection to propagate onto the orb array.
You'll know you can kill it when his ball turns green,
and his cursors look just like the infected cursor
on the achievement thumbnail.

Windowchill
reach the end of timed mode

If you haven't unlocked 'timed mode' yet, have a look at the 'Game mode' section in the index on the right. Then, all you have to do is survive for the 20-minute countdown.
Same advice as endless : pick a character you're comfortable with, try to understand how to defeat each boss safely, and keep enough gold for healing when you're low.



Windowbreak
get a x4 multiplier

'Multiply' is an upgrade you can buy in the shop. To unlock this achievement, you need a x4 multiplier. What I understood from it was that you need to buy 3 'multiply' upgrades in one go (1 upgrade = '+1', you start at 'x1' so with 3 upgrades you end up at x4).
What I advice you to do is to lock it in the shop when you see it, and then 'restock' the shop or buy other items until 3 of them are aligned :













When you bought 3 of them, just resume the game to get the achivement.



music track: windowshatter
recover a mebo 100 times

For this achievement, you'll need to unlock the character mebo beforehand. As always, feel free to check the character section of this guide for tips on how to get him.















If you've played with mebo before, you're probably familiar with the '+1 mebo' upgrade available in the shop when you play him (pic1). When bought, you will be granted an additional playable character that can shoot and be shot. If one of your mebo is shot, it will be defeated and turn into a ghost, but you won't take any damages. Once each of your clones is defeated and only 1 mebo remains, you will start taking damage if you get hit.
However, you can recover a ghost-mebo by letting him recover in your own mud. In other words, try to bring a defeated mebo close to one alive to revive him (when you're no longer attacking, all your mebos will try to join each other and respawn).
The goal of this achievement is to do this a hundred times.
My advice for this is to start an endless game with mebo, try and get a single '+1 mebo' upgrade as soon as possible, and then stop attacking (so your characters stay together and heal), and purposely get hit until your mebo grows back almost instantly. If you do it right, you should be able to get the achievement in no more than 3 minutes of running away in circles.

nyx skin: hector
get lv. 4 halt

This achievement will give you access to a special skin for 'Nyx'. Therefore, it is required to already own the character 'Nyx' to unlock this achievement.
If you haven't unlocked 'macos 10' yet, I recommand that you read the part of the guide where I explain what it is about, as it also requires 'halt', so you may want to unlock it at the same time as this one.


This one is pretty straightforward. You will need to start a game as Nyx and kill enough bosses to buy each of the 4 upgrades. You will need a total of 10 (1+2+3+4) stars. If you are struggling because of Nyx, I recommend going for 'multi-shots' and 'fire rate'. Remember to always keep enough coins to buy heal at any time.





:) skin: XD
keep a smiley alive for 10 minutes

Pretty self-explanatory, you will start an endless game and wait until the boss 'smiley' spawns. As a reminder, here is what the boss spawning pattern should look like:

1. Spiker (≈2min)
   
2. Wyrm (≈4-5min)
   
3. Slimest (≈6-7min)
   
4. Smiley (≈8-9min)
   
5. Orb Array (has a random chance to spawn after Smiley, >10min)
   
6. Infection (Miasma) (has a random chance to spawn an infected triangle)

Take a character you feel confident playing with, kill the first 3 bosses, and Smiley should spawn around 8 minutes in. From now on, ignore him; it's easy to keep him alive since you can only damage him by closing his window. He will alternate between restricking your game window and attacking; do your best to survive!



mebo skin: constellation
kill miasma as mebo without getting hit by its splatter attack

First of all, this achievement requires playing with the character Mebo; therefore, you will have to unlock him beforehand (check the 'character' section of the guide).
Then, you'll need to get pretty comfortable playing with him, because the achievement is about beating the infection (aka Miasma) without getting damaged by it.

If you're struggling, here are some tips:

• Seek the shop to save some good temporary updates (the ones with curved edges). The goal is to focus on Miasma to kill her as soon as possible. Those boosts that last for a few seconds and 
  it's perfect for what we're trying to achieve. On my run, I manage to have 2 bubbles (which makes you invincible).
  
• Before killing the infected triangle and releasing Miasma (therefore exposing you to her attack), be sure to kill the current boss if there is one on screen.
  
• If no boss spawned in a long time, you may consider waiting and killing the next one rather than him spawning during the infection. The point is: you don't want infected (stronger) bosses for the whole time you're trying to defeat her without getting hit.
  
• In the same state of mind, you want to buy and wait out for your special perk to be ready at the beginning of the fight.

Note: I'm pretty sure that being 'hit' count as loosing an HP. Therefore, the more mebo clones you have the better. Remember to stop attacking and 'heal' your mebos when only a few of them remains.

Edit : just a precision made by @Qwergin in the comments : you don't need to do it no-hit. You just can't get hit by the splatter attack which is the goo that will hit you unless you go to the small safe spot.

Serenity
die to slime trail


Start an endless game and survive until the slime appears. It is the 3rd boss of the game and should appear around 7 minutes into the game. The Slime will summon targets that follow you and leave behind some green trails that inflict damage if you stay in them.
You will unlock this achievement by staying in and dying from his green mud.

Friend
Secret achievement

This might be is the hardest achievement of the game : you need to defeat the secret boss ':)' without taking any damage during the whole fight. You can take damage before the fight; it won't matter. If you do not know how to summon the secret boss, you can check out the 'character' section of this guide and read the ':)' achievement.

The main thing you can do to make the fight easier is to choose your character wisely, considering that only the perk matters because your attack will change before the fight. I recommend using Zephyr's dash to dodge the boss's attacks.
Additionally, I've heard from some people that reducing the game scale helped them; you might want to give it a try. Before the fight, you can try buying speed upgrades, but when I did, I bought up to 'speed lv. 12,' and I'm pretty sure it got reset at the same time my weapon changed.

Edit : I finally got the achievement! Here are a few more tips:

• I confirm that playing in x0,5 helps a lot for me! You can change the scale in 'settings->windows', then enable 'fake windows' and you can choose the scale of the game. You will have to do it before breaking the window, you will not be able to change it afterward.
  
• Not getting hit is more important than dealing damage, focus on dodging, attack when you're safe.
  
• Every time you hit him, he will throw the window back at you. Take advantage of that : learn how to stop the window close to you, ready to shoot him again. But if you're too close to him, you may want to avoid hitting him, because you will not be able to stop the window if you're too close.
  
• If the window is too far from you, don't bother trying to reach it, there is a great chance he will throw it at you before you can even reach it. Focus on doding and get ready to stop it.
  
• Finish every fight, even when you get hit. It takes 6 minutes to get to the boss, so once you're there you should train to become more consistent !
  
• Some attacks are easier than others to deal with. Once you start getting many 1-2 hits run in a row, keep going until you have a good RNG, you're almost there!!

I hope this helped, Good luck :)

Here is the footage of me beating him, unfortunately it didnt record my beatuiful backgrouond :(

[4.0 Update] I don't know if this will be patch, because I'm writting this really shortly after the realese of the 4.0 Update, but if it isnt patch, this might no longer be the hardest achievement in the game. Here's the thing :
This new update added a new character, mebo. This character has the unique ability to multiply himself, and to be able to tank damages, and heal himself, without being considered as a hit by the game.
What happend to me when I was trying to get the "kill ??? as every character" achievement with mebo, was that I triggered him in a pretty late game, with a lot of '+1 mebo' upgrades.
This ended up being one of the easiest fight, because I kept all of my clones, and all of them were given the powerfull 'bubble' weapon. On top of that, even while being afk I couldnt get hit by the window because I had too many mebo clones to protect me.
Anyway, if this isnt patch, the way to go is to buy as much as '+1 mebo' upgrades as possible, along with a lot of 'regenaration speed' upgrades. With that, you should be good to go!





























Crown
Unlock everything

This achievement will likely be your final one. It will unlock once you have earned every other achievement (except 'Friend'). Congrats ! Take the crown as your final gift :)

- - -
I hope this guide has been helpful to you. It's been a fun first-time experience for me, and I've learned a lot ! If you noticed any mistakes, something missing, or anything unclear, I would love to hear it and update the guide !

I would like to thank Ruby01Games, and everyone who provided precious information in the comments under this guide during the 'work-in-progress' state.
Also, special thanks to Kornichon for supporting me in this project :)

And most importantly :
Thank you for reading it !
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