Thank you TengenToppa! Perfect review IMHO. This is probably the best DLC I've ever played, even if it is a little pricey. On the other hand, my GF and I both play Skyrim and I was happy to see we only had to buy the DLC once to play it on both our Xbox profiles (this is not often the case for DLCs). I love how Dawnguard adds not only a new questline, but new elements to the whole game, making it a gift that keeps on giving. The undead horse that you can summon is probably my favorite addition. I like to travel on horseback when I'm on the road, but if I want to venture in to the wilderness, I prefer going on foot. This summonable horse allows me to switch whenever I like and on top of that, it can't die so I'll never have to buy a new one.
I also get the impression that Bethesda took some inspiration from Bioware in the way they handled the character of Serana. She always has new things to say and new dialogue options become available to learn more about her past wheneve you like. That reminded me of KOTOR and DA:O.
If I have one complaint, and it's really a very minor one, it's that the armored trolls are not as useful as I would have liked. They tend to get stuck in narrow corridors and they die easily. That's about the worst I can say about this otherwise fantastic DLC that really adds a great deal to the game. Can't wait for the next one
