Mastery can be earned by defeating the final boss while only using your sword. Do not throw your knife or spear. You can watch this be done at 101:00 in the video below.
A few tips for this fight and situation. The game is not over when the final boss is defeated so try to make sure you have a tonic in your inventory from the last camp fire which is quite a few fights previous to this. You may be bleeding after your fight and if you want to see the end of the game and have a chance to continue without resetting progress to work toward the "Bloodlust" achievement, you could likely love having a tonic so you don't have to fight the boss again.
This guy is tough and has a particular attack that will likely kill you instantly.
If you are not the most skillful and reacting to his prompts, perhaps try what I did below:
The best method I found to defeating the final boss was a high attack () and then quickly stagger him with a shoulder check (), then take advantage by attacking again. You can get a rhythm with a bit of practice to chain these two moves over and over. If the boss gets away from your combo, try to induce the situation again by sneaking in a shoulder check after you land a high attack. Also, at the very beginning of the fight, if you are quick dropping down to him, you can get behind him for a free attack, this is a good way to set up your first combo of and . You should have success stringing the combo together as long as you dont get close to walls, that can throw it off.
(This cheese method has been patched)
Since the Cheese Method is likely not gong to work for you, you are gonna have to do this one with skill! Take the time to try and learn his attacks and indicators of where you can get an attack in. The video posted shows combat with the boss that can be studied to set you up for success and then will like take some repetition and improvement until you finally break through and defeat him. My advice would be prioritize your own health and not get into a situation where you open yourself up.
You can also make sure the the combat is set to "Assist" in the settings to make combat a hair slower and easier.
Maximum Armor will help as well to ensure you can take a little punishment. If you are traveling up to the final boss and have your armor piece break, I would let that enemy kill you, so that you can respawn with that armor intact.
For all achievements in the game, you can follow this awesome guide on YouTube:
All credit to Trophy Tom. Please like or subscribe to support him. Please note how he has conveniently labeled sections of his video based on which achievement is next or what item you are tracking down, this can be seen if you watch his video on YouTube on the video progress bar instead of the imbedded video here on True Achievements. It is a very well done 100% guide.
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