How to Get the Drake Sword in Dark Souls

Prepare for your fight with the Hellkite Wyvern by purchasing the items required from the male undead merchant in Undeadsberg. The trader can be found near the bonfire in Undeadsberg, underneath the two spear Hollows and sniper, before you reach the area with the firebombing Hollows. Break the boxes after defeating the spearman and go down the stairs. In this room, you will see a bookcase to your right. Be careful, as there is an ax-wielding undead behind it. In the doorway right in front of the stairs, you exit and there you find the merchant on the balcony. If you don't have one already, you will need to buy a bow from the trader for 600 souls and a few arrows, ranging from 3 souls each to 50 souls each.

Make your way to the large bridge after your fight with the Taurus Demon Boss, later on in Undeadsberg. After you pass through the tower the Taurus Demon jumped off, you'll find yourself at an area with the knight Solaire of Astoria to the left and the large empty bridge ahead to the right, with a few Hollows on it.

Walk onto the bridge and trigger the appearance of the Hellkite Wyvern. If you begin to walk onto the bridge, after a while you will trigger the appearance of the wyvern, who will roar and immediately burn you to a crisp (along with the Hollows on the bridge). Try running back to the beginning of the bridge to avoid dying, although if you're not quick enough, this will probably be inevitable.

Sprint halfway up the bridge. This will trigger the Hellkite Wyvern to begin breathing fire upon the bridge, but you will notice there is a flight of stairs to the right of you leading down from the bridge. If you are fast enough you should reach this area before the wyvern's fire kills you.

Roll down the stairs quickly before the fire kills you. You will now be underneath the bridge and safe from the wyvern's attacks and be in a room with two exits.

Enter the door ahead which will lead further under the bridge. You will notice a series of bridge arches and small paths either side. There is another door to the left which leads back to the Undeadsberg bonfire.

Kill the two Hollows underneath one of the arches under the bridge as you move along the narrow paths. There will be one swordsman Hollow and one with a spear.

Look for the Hellkite Wyvern's tail. If you stand on the right pathway in the bridge arch where you killed the two Hollows, you will be able to see the wyvern's tail swinging to the right of the bridge ahead.

Equip the bow and arrows you bought from the merchant in Undeadsberg. You can do this by entering your character's item menu and equipping them to your character's left or right hands, and by equipping the arrows to your quiver spaces.

Enter long range aiming mode with your bow. This can be done by drawing the bow and pressing the LB button on your Xbox 360 controller. You will now have a large cross-hair on your screen which shows where your arrow will be fired.

Aim at the Hellkite Wyvern's tail. Because of your distance and the weight of the arrows, you may need to aim slightly above the wyvern's tail to make sure they hit. Also, you will have to time your shots well as the tail swings quite quickly back and forth.

Wait for the Hellkite Wyvern to return to its position on the bridge. After you shoot the wyvern's tail, it will fly to the bridge above and try to find you. After a few moments, it will return to its position guarding the bridge and the tail will be in the same spot as before.

Repeat shooting the tail until you receive the Drake Sword. If you continue shooting the wyvern's tail, after 20 or so shots (determined by your weapon damage stats and the size of your arrows) you will see a screen prompt saying you have received the Drake Sword. Congratulations!