Are you tired of getting your zhopa beaten recklessly time after time by an invincible Penis Detrov with his sword, rabbits and microwaves attacks ? Just reduce his health a little bit by using the following method. You will need to have both the game and the software opened simultaneously.

1) Download, install and run CheatEngine (it's free you poor shakal ebanij.

2) Select the process "Valakas Story.exe" or some title like that.

3) In the game, load the arena with Deniska, skip the cutscene and approach the enemy. Enter combat mode (RMB) and lock the target (Q key) and Denis health bar will appear next to him showing 10,000 Health points.

4) Now Press ESC to pause the game, press the windows key on your keyboard and open the Cheat Engine window.

5) Make sure you selected Valakas.exe as a process, type "10000" in the value field (right hand of the screen) and click "first scan". It will show a few lines, good. If not, repeat the operation at step 2 until the correct process is analyzed.

6) Go back in the game, give a few punches to Deniska and press ESC quickly again.
Note the current health of Denis after your punches (let's say 9950), and go to the Cheat Engine window once more.

7) Replace ALL the 10000 by the current health (9950) and click "Next Scan". It will show you a few updated fields, change all these values to whatever number you want (not less than 10, since lower values may crash the game), and Deniska's health will be updated.

8) Now back to the game kazyol, beat the hell out of this dolbaeb and you're good to go.

tldr : got tired of spending 2 hours + on the final fight, just for loosing at the last 200hp of the boss, so decided to fix the difficulty. Another way was to reduce the damages dealt by Deniska, but it require 3 more operations so fcuk this, le'ts make it simple.