Well, I was trying to do what @Fzanco (I hope I got their name right) was doing. Full lvl 2 Fenris set (but additionally with fire protection potion), Lvl 3 Frostner, Lvl 3 Black Metal shield. I also have the bow with me (Lvl 3 Draugr Fang with 20odd frost arrows and 60odd needles). Also the Black Metal atgeir (Lvl 3) for mobs.

I'm not a fan of digging moats or under altars. I just plop my portal down, hop over and start the fight. If things go south, I jump through the portal, pick me up and continue the fight.

That's how my last boss fights have been. Usually die once during the fight.

As said, it's a middlish island. His spawn point is very close to a bay in the north east.

Seed is Pct2NspXkR.

Edit: I usually try to contain the boss to their spawn points as much as I can to not draw unwanted attention from the other denizens on this island. So far, this has worked out pretty well.

Edit2: I also have a full lvl 3 padded armor set with me, if need be. But I'd like to keep the fire protection of the Fenris set.