First of all - Back Up Your Saves! (just in case)
Saves' path is at: C:\Users\#####\AppData\LocalLow\Steel Mantis\Valfaris\long number folder

My saves can be downloaded from: https://drive.google.com/file/d/1tc-7Tyouk-KZpVyH6K4od7BuT9xD_Lhs/view?usp=sharing
Now, move a save file you need into the folder and rename as "Valfaris_Slot_0".

Eight Worms A-Leaping
Kill 8 worms jumping out of lava river. Memorize the directions they attack from.

Giddy Up!
Jump at a Stone worm and melee him, so he accelerates 10 times.

Select eponymous files from "Certain Areas" folder and move\rename them as mentioned above.

That’ll Leave a Mark
Pre-fire once at the spiked ball and shoot again when the boss is moving towards you.


Coup De Grace
Kill Furrok with his own hammers. Do that at the end of his health bar and instantly jump to a candelabre, as the boss will ignite walls.


Select files from "Boss Fights" folder and have fun.

Right Back ‘Atcha
Select "Level 3 The Hive", reach the secret area with unlimited energy, then keeping your shield active all the time simply stay in one spot, redirecting their charges.

Headbanger
Parry Hydravok’s heads 3 times in a single life. Each parry uses 75% of your shield.
Make sure you do some melee damage to replenish the energy. Watch from 01:15.

Sparks Will Fly
Special Thanks to player Hibachi who highlighted:
"They're the purple things with four sides, that have lasers shoot railguns. You find them in the part where you have to open two doors. Bring the Hellhammer."


Bringer Of Darkness
Destroy 70 lights. They can vary in shapes and colour: mostly flat blue and yellow, but also bubbly blue. Look out for them from the very first level.