Alduin was dead. Tsun and I saw to that ourselves. He taught me the Thu'um to go back to Tamriel and I used it.
The next thing I knew, I was back home in Whiterun, but I wasn't done with my quest. Skyrim had a civil war to win, the Stormcloaks were counting on me. Winterhold has a college that I need to get back to. Lydia wants children. Not until I get Hearthfire. And a black warrior stood at the Town Gate, but every time I get a good glimpse of him, he's gone. A whisper carries a sound on the wind, always hissing "Eighty, Boy. Eighty.".
Walking into my home, I recognized two things: One was that Lydia was not there. Another was that the Dwarven sword I mounted on the wall was also gone.
"Damn it," I said to myself, and went out the way I came.
Half an hour I bursted into Dragonsreach, storming up its stairs and straight to Balgruuf. Irelith tried to stop me by putting her sword to my neck, but I moved it with but a finger.
"Lydia," I interrogated. "Where is she?"
Balgruuf said nothing for a moment. Then, right when I was about to put on the mask and light him up, he stammered.
So taht was this thing's name. Nice.
"Hurry to Shearpoint. Your wife headed there, and there have been sightings of Dragons in that area."
I ran out of Dragonsreach. Lydia was probably already dead, but did that matter?
I jumped from the stairs, and Ohdaviing's wing caught me as we flew toward Shearpoint at top speed.
Another dragon was surely there, but it didn't matter. I was already upon it.
Heaving my sword into its back, I gave a hearty shout. Lydia looked up at me while hiding behind a pillar.
I jumped from the Dragon just as Ohdaviing flew off with its half-dead carcass, carrying it by the neck.
"Shh!" She warned. "You'll wake it!"
Wake it? What the hell?
At that moment, a coffin in the distance went BOOM and sent the lid flying in our direction. From it arose a skeletal being draped in gold.
And it was carrying a mask just like Nahkriin.
"Nahkriin," it wheezed.
Lydia looked to me in surprise.
"What are you looking at it for? Kill the damn thing! It won't look any different with an arrow in its head!"
With that, I lit blazing flames in each hand and charged at it. This thing was really fast, evading all of my attacks, but I had the upper hand. I was going to kill this thing.
"FUS RO DAH!!!"
The unrelenting force blew the creature into a wall. This was my chance. I took out my sword and lit it ablaze. I ran the thing through, making it scream in agony.
"Krosis..." it wheezed.
"I'll be taking that," I said as I took the mask from its face.
"Krosis!!" It yelled, reaching for the mask. I snatched it away.
So this thing was Krosis, eh? That's two, then. I looked to Lydia and she gave me the sword from my wall.
"I don't want an explanation," I began.
"I just want to get home, and find out what these things are..."