I finally fought Manus; Father of The Abyss the other night. I was in the fight with Sif's spirit companion...
Actually let me take a moment to tell the story of Artorias The Abysswalker in a very condensed form, so this post will at least make sense to anyone who doesn't play Dark Souls. Oh and SPOILER WARNINGS to anyone who hasn't gotten this far in the story...
Artorias was one of four knights sent by an old King dude named Gwyn, to do some stuff. Artorias was supposed to go to the Abyss (a big hole of darkness seeping into the realm of mankind from deep underground.) Artorias had a Wolf buddy named Sif. They were hell of close. Sif would do anything for Artorias. So anyways, Artorias eventually ends up in The Abyss (via a magic ring, which I forgot the origin of) where he's fighting some evil dude named Manus who used to be a human, but is now responsible for spreading the Abyss into the surface world. He's pretty much kicking Manus ass, when he breaks his arm, and basically gets screwed out of victory. So before Artorias gives himself up to the corruption of the Abyss, he puts an enchantment on Sif protecting him with a magical ward, but putting Sif into hibernation at the same time. Artorias continues his fight, and ultimately turns into a puppet of darkness (my apologies to Vaati, or any other Dark Souls Lore expert. I probably butchered that to hell).
Enter your players character. The DLC setup is way too convoluted to explain, so just know that for reasons Manus has yoinked your ass back in time to his time, and now you are making your way (the only way you know how) to Manus lair, where you will try to do what Artorias failed to. Along the way you can come across Sif still all hibernating under his ward. But when you free him, you can summon him into your fight with Manus.
Soooo... last night I did just that. I summoned Sif into my battle. it was grueling, we both danced around the darkened arena trading attacks, and just as I was about to make the killing blow to end Manus reign of terror, I was felled by his evil hand. And as the crimson words "YOU DIED" faded so familiarly onto the screen, I saw Sif in the background take one more swing at that rat bastard!!! In my throes of death, Sif both avenged me, and avenged his companion Artorias. As my view faded to black, I saw Manus disintegrate into a mass of souls, and I caught a glimpse of the reward he dropped. It was a poetic moment. It was pure Dark Souls.