Your quicksave is useless as i can´t fight for you. I killed him yesterday and had no problems at all. In this moment i´m preparing for Tayasal and will finish the game tomorrow.
1. You can´t use normal weapons for the Guardian, you can only use the magic dagger on him
2. You have to prepare yourself with a lot of Elixir (i use 50 bottles for the whole Ksocheatem), Ometochli Tincture (about 10) and Tears of Ixchel (2 or 3) to recover your health afterwards (all this is always important for TEHO fights!)
3. Your Health should be Excellent before the fight
4. The only weak point of the Guardian is, that he can´t run fast
5. You have to attack him with group attacks while using Ometochli Tincture (that destroys him very fast) till your health goes down, then run around in circles (only fight him at the beach where you have enough space to move) and try to stay away from flames and recover your health
6. Always use quicksave when you were successful killing him one time and he is recovering. Always keep running around the beach till your health is recovered and Ometochli Tincture is available again
7. You can more or less ignore the other skeletons because they don´t have much power and disappear after some time or die during your group attacks and they are so stupid that they run into flames when they follow you
8. I don´t know how difficult that fight is in Hard mode but in Normal mode it´s possible. You need to have patients for that because you have to kill the Guardian 4 times till he is giving up
9. In the end he will keep the dagger, so make shure that you don´t have to fight other left skeletons afterwards because your normal weapons are useless here
10. This is all help that i can give you, the fight you have to survive on your own
Good luck again!
BTW:
From Rocky Cove to Shark Beach you have to sail to the right and better never reload your game at sea here or you will get into very rough waters. I always defeat the spanish fleet with nice exploding mine carpets while peacefully sailing to Shark Beach and they sink one by one behind me, as they deserve.
I sold already 58 from 88 chests today. A hell of a job but i had to go shopping for Tayasal anyway.