In my opinion, Bloodmoon's last quests are insane. As soon as you encounter werewolves you'll notice that you are in a big mess if you're not well equipped and leveled.
In the very last quest you will encounter a LOT of 700 hitpoints very hard hitting wolves (the frostmoth's captain was slain in the first seconds of the first fight) - for me, they were the hardest enemies in the whole game. Dagoth Ur, Almsivi were all a joke compared to those. I ended up going through the very last quest entirely invisible.
They are fast, they hit for hundreds of damage and usually come in packs of at least 2.
I suggest you go Morrowind -> Tribunal -> Bloodmoon to not get frustrated by the ridiciously strong enemies (or enchant a 100+ sanctuary suit).
Seconded. I had 18 points health regeneration, about 250 points of damage reduction/armor class, 100% magic reflection and was pretty much invincible to anything on Vvardenfell, no matter the enemy there I could stand and take its beating just hitting it like once or twice when I got bored of watching them hit me to destroy them.
But then came Bloodmoon, man I never expected to die ever again so I didn′t have any health potions, big mistake. Since I sold all of my health potions things just went downhill quickly in the last part of the Bloodmoon main quest and I died once against 3 werewolves and was on edge after reloading the save while doing the place again taking great care never to fight more than 2 at a time.