100% Achievements and other unlocks

How to unlock everything.

Achievements

It should be noted that achievements can be obtained in both Casual and Veteran difficulty.
Ultimate mode can be used as well when available.

Endings

Nightmare's End
Finish the game without sacrificing or recruiting any adventurers.



Those Left Behind
Recruit every adventurer and finish the game.



Fallen Moon's Requeim
Finish Nightmare Mode.


Unlocking this ending requires achievement Those Left Behind.

Emperor of Darkness
Sacrifice every adventurer and finish the game.


Kill all adventurers.

Blade Gleaming at Sunrise
Adventure with your allies and see the Normal ending.


Recruit at least one, and at most two adventurers.
This ending has slight variations at the ending scene and epilogue depending on who do you recruit. This has no effect on the achievement and can be obtained with any combination.

That Man, Zangetsu
Go it alone and see the Normal ending.


Don't recruit anyone and kill at least one, at max two adventurers.
You can kill and ignore any combination of adventurers, it will have no effect on the ending scene.

Stages

Moonlight of Temptation
Finish Stage 1 for the first time.



Frigid Hell
Finish Stage 2 for the first time.



The brilliant Void
Finish Stage 3 for the first time.



Blasphemy unto Heaven
Finish Stage 4 for the first time.



Sunder the Night
Finish Stage 5 for the first time.



Tragedy of Slaughter
Finish Stage 6 for the first time.



Defiler of Taboos
Finish Stage 7 for the first time.



Cleave the moon
Finish Stage 8 for the first time.

Boss Rush

Big Game Hunting!
Defeat every boss in Boss Rush mode.


Unlocking this mode requires achievements Those Left Behind and Emperor of Darkness.

Modes

Nightmare Mode
Unlocking this mode requires achievement Those Left Behind.

Ultimate Mode
Unlocking this mode requires achievement Emperor of Darkness.

Boss Rush
Unlocking this mode requires achievements Those Left Behind and Emperor of Darkness

Conclusion

If you followed these instructions you should now have all the achievements in the game.

Now you just need to wait for the real game to come out.

Bonus

Special death screens

If you fail to defend Alfred on fight against Zengetsu you will be met with this special death.

Credits

I made this guide based on discoveries of mine and others on this thread:
https://steamcommunity.com/app/838310/discussions/0/1694922526900156950/