Dawnguard is a faction of the Elder Scrolls V: Skyrim game. They are a group of warriors who are dedicated to fighting vampires. You can easily join the faction by following these steps.
Steps
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Step 1. Reach level 10
This will start the chain of events that will allow you to become part of the Dawnguard.
To reach level 10 quickly, complete missions given to you by non-player characters from the world of Skyrim to earn experience and gold
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Step 2. Travel to a city of Skyrim
Any major city will do. You will trigger the first event.
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Step 3. Look for a man named Durak
You should be able to find it by walking around the city; usually it will be close to other people.
You can read a person's name by pointing the camera towards them
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Step 4. Talk to Durak
You can do this by pressing "X" (PS3), "A" (Xbox 360), or "E" (PC). When you talk to him, the Dawnguard mission will begin.
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Step 5. Reach the Dayspring Gorge area
You'll find it southeast of Stendarr's Light, which itself is southeast of Riften or south of Giant's Grove. Check the map by pressing "O" (PS3) "B" (Xbox 360) or "Tab" (PC) then going to "Map" at the bottom of the menu.
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Step 6. Talk to Isran and Guardian Tolan when you reach Dayspring Gorge
Usually, you will find Isran on the second floor of the fort or inside the patrol fort during the day.