Happened to me, a master Vampire, his thrall, 2 death hounds and a theif. I was too late to save the smith, Tragic. Anyway lets here your tragic attack stories!

i had a thief attack in riften when i downloaded dawnguard, i hope to god i didnt have a vampire attack at the same time and didnt notice
well, doesnt matter anymore im not playing skyrim again because of the attacks

Vampire attack and dragon at the same time.

Strange thing is that I shot the dragon with an arrow, and poof! he disappeared.

Heard some fighting going on in the center of town so I ran over to see what it was. As usual the guards were attacking a thief, so I just waited for it to end so I could go loot the thief like I always do. That's when I noticed the dead Master Vampire on the ground next to him. All npcs seemed to still be alive so I just went on about my business. Just another day in Riften...

I had a vampire attack and a challenger showed up for a duel lol.

I just finished the imperial quest line for the civil war so the imperial guards started killing the riften guards when I entered,BUT not just that a thief,2 master vampires and their thralls,and a blood dragon spawned at the SAME time!Everyone was getting massacred even I got killed.

I hate the [censored] random attacks in cities and towns, it's so [censored] pointless, it just completely wipes the game of NPC's. Especially when you get to higher levels and you start getting ancient dragons attacking towns. I don't know why on Earth Beth thought it was a good idea...

cocaine my friend, cocaine

riften, whiterun and riverwood seem to be the most common targets of vampire attacks

I had two mobs of vampires and a dragon attack Falkreath. Luckily there were no casualties, the guards and I ate the vampires before the dragon showed.

This.

The guards made fools out the Vampires, and then after a well placed Marked for Death, the Dragon was quick to follow.

Body Count: 2 Guards, 1 Dragon, 2 Master Vamps, 4 Thralls.

My coolest encounter is when I went to the orc stronghold SW of Riften to deliver the Daedra Heart and Troll Fat for the Malacath quest. A giant was attacking again while a dragon spawned overhead. I took out the giant then turned my attention to the Dragon. While fighting it if find I am getting whacked by someone else. I turn around and there are three vampires! Holy Cow Batman! One of the coolest fights I've been in.