Hitogata Happa is one of those games that have no tutorial, nor any guide to help you get started. Therefore the game may seem impossible due to 2 things. 1. The game is hard, there is no getting around that fact. and 2. There are parts of the game mechanics that was never explained. This saddens me as it is a really fun game once you get the hang of it.

Here i will try to explain the basics of the game mechanics so that its only the hard part to worry about.

What are these dolls and how do they work?

The dolls are the characters you control they act like characters usually would in a bullet hell game.
They move(arrow keys) Shoot (z) and and have a special ability (x), what makes them special is that all of them are also bombs, that's right, bombs. After you fill up the flow charge gauge (top right bar on the screen, you will see a tiny message over your doll saying "bomb ok" and the bar on the top right of your screen will say "FLOWMAX" this means the bomb is ready. When the bomb is ready you can charge into an enemy, blowing yourself up doing so to deal immense amounts of damage on the enemy. You will lose a doll for it but unlike just getting killed you will not lose gems for using bomb attack.

The bomb attack is also known as "Hitogata Happa" which is also the name of the game, this is Japanese and means literally "Humanoid Explosion", which is how it is translated in the manual. Hitogata can also mean doll(which would probably be a better translation in this case), if humanoid explosion seems to morbid for you. Happa which means explosion can also be translated into leaf, which is probably why the doll with the most powerful bomb attack is called leaf(as a pun, laugh dammit)

One final note about the bomb attack, the bomb attack will only work if you ram directly into the enemy. Hitting a bullet will cause you to die without activating your bomb attack even if you have full flow(FLOWMAX).

When starting the game i highly suggest playing on the easiest difficulty. This makes the enemies a bit weaker and gives you infinite dolls for the first mission(though only leaf dolls). The amount of dolls you have is the number of lives you have, so this may seem like you cant lose. You can, and probably will lose even with infinete lives, i'll explain how in the boss part.


CONTROLS
The game is played by using:

The arrow keys - Movement
Z - Shoot [Reffered to as "BUTTON A" in game]
X - Special Ability [Referred to as "BUTTON B" in game]
C - Change what doll becomes the next doll after this one dies[Referred to as "BUTTON P" in game]
A - Pause menu

PS:C is not used in the fist level as you only have leaf dolls
PPS: in the short period when waiting for a new doll to spawn you can also select the next doll using your arrow keys.
PPPS:Shooting slows you down so dont hold in the shooting button all the time as this will severely restrict your movement

INTERFACE

The left panel:
on the bottom is the next doll(the one you'll get after this one dies.
above that is your current doll.

The right panel:
a list of all your available dolls, the one with the blue circle next to it is the doll that you have selected to be your next doll(with C).

The game screen:

The top left is your score
The top middle is your mana(you use this to use your special abilities.)
The top right is your flow(this is what you charge up to use bomb attack.)

The bottom left is your gems you use theese to buy new dolls
The bottom right is a FPS counter, it tells you how fast your computer is running the game.

THE ZOC (ZONE OF CONTROL)

When you start the game you will notice that the enemies have rings around them. This is their ZOC. This does 2 things. 1. When you kill an enemy, all bullets that are inside thet enemy's ZOC is destroyed with it.(this gives you extra gem drops for each bullet). and 2. If you are inside an enemy's ZOC nearmy enemy bullets gets slowed down.

This is probably what has scared most people away from Hitogata Happa. If you don't know about all parts of the gameplay it is seemingly invincible because your normal attacks barely do damage.
So now I'm going to explain how to approach a boss situation like this.

Firstly, when you enter the boss stage you will notice three new bars, a yellow one with a blue one underneath and a timer to the right these all on the top of the screen, along with a red one on the bottom of the screen.

The red one is the health of the boss body part that you are currently attacking.
The yellow one is the boss' total health left
The blue one is time left until the boss enters "Error Mode"
The timer is the same as the blue bar except that it is shown in seconds.

This so called "Error mode" makes the boss almost unbeatable. It does 2 things. 1. It makes the boss' attacks unfairly hard. 2. It allows the boss to OHKO(One Hit Knock Out) you. Meaning that if the boss kills one of your dolls you lose the game no matter how many dolls you have left.(Remember me telling you about losing the game with infinite lives, this is it.) Bomb attacks doesn't count as kills.

Now you may be thinking that this "Error Mode" makes the boss unbeatable. Unfortunately that isn't too far from the truth. It is still possible to beat it, but that is most likely just a far dream for a newbie. So for now lets focus on killing the boss before it enters "Error Mode".

The way to attack is pretty simple, dodge the boss' attacks until your flow charge is full. then use bomb attack on its arms. But be careful, when the boss' arms are glowing they count as a bullet. not an enemy, meaning ramming his arms while they are glowing will cause you to die without activating bomb attack.

After both his arms are gone, the "shield" of bullets around his head disappears allowing you to use bomb attack on his head, so that is obviously what we are going to do.

PS: Leaf's(the doll you have on the first stage) special ability is slowing down time. This is very useful for dodging bullets when charging the enemy to use bomb attack.

Even with all this, don't expect to do it on the first try. But you will notice that it becomes far more possible now. After a couple of tries you should probably do it.

After the boss is finished you no longer have infinite leaf dolls, now you have to spend the gems you have acquired on dolls. different dolls are good for different things, for example:

Leaf has the most powerful bomb attack but apart from that is pretty weak.
Earl is amazing against huge numbers of weak enemies but not as good against strong enemies.
Peco attacks with swords and only hits close targets but do a ton of damage.

You will probably get your own favorites after trying them out for yourself.

Enjoy Hitogata Happa!

This is my first guide and i would appreciate comments with constructive critique.
English is not my first language so if there are some grammatical mistakes feel free to point them out and i will try to fix it.