- I'm pretty sure that vampires will only spawn in a city/town if you are in it
- If they will spawn it will be within the first couple minutes of you entering the cell
- they will more often spawn during the night than day
- fast travel less frequently (as people already do due to dragons)
- When you enter a city hang around the guards by the gate for about 30 seconds
- try and get the vampire to focus on you, a follower, or a guard
Not according to other accounts of open cities or ones with multiple entrances. Solitude for example, they can appear from different entrances apparently meaning they will have slaughtered half the district by the time you reach them. Depending on their level they can easily 1 shot most NPC's.
And you should not have to rely on reloading to do this. The frequency of attacks means reloading will become natural to playing and it shouldn't be.



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. there is a bug that a lot of people are getting that causes the attacks even after the main quest is over. there is also reports of one that causes attacks if you even pass by the city. This is a problem and players should have to figure out a "work around" for something that is the DEVs fault