Undead Dragon Information
The Valley of Drakes dragon is located near a wooden bridge close to the New Londo Ruins entrances. He's guarding three items, an Astora's Straight Sword a Dragon Crest Shield, and a Soul of a Proud Knight. This mini boss is completely optional and will not attack you until you go to pick up one of the items he is guarding. The Astora's Straight Sword and Soul of a Proud Knight can be acquired safely without aggroing the dragon. You do not have to fight any of the Drakes in the valley in order to get to this boss either, just run left past the first drake after entering the valley through the elevator from the Darkroot Basin and dash forward past the second drake on the ledge. The drakes wont follow you up the path, so you have no enemies to fight between the bonfire and this miniboss.
A second Undead Dragon is found blocking the bridge in The Painted World of Ariamis. He's guarding two items, the Bloodshield and a Large Soul of a Proud Knight. This dragon is also optional, but it provides a shortcut to the boss area, if you for some reason would like to avoid the enemies of the level's underground area. After this dragon is defeated its hind part will be left behind on the bridge. The dragon's remains are similar to the bounding demons of izalith, but totally harmless. To be able to pass under it you have to do a jumping attack (Forward+R2/RT) to make it stand up.
- Toxic breath: The dragon will breathe toxic waste towards you if you stay out of its reach. If infected you will lose 7HP/s for 10 minutes, or until cured.
- Claw swipe: Swipes its claw horizontally. Short ranged attack.
- Bite attack: Lunges head forward and bites. Medium ranged attack.
- Acid Bath: Spits a pool of acid that breaks your weapons and equipment.
Easy ranged strategy: If you have enough arrows, you can sit back and shoot at it until it dies. Typically, it will not be able to fight back, as it is stationary.
Easy melee strategy: Two hand your weapon and make sure you can dodge fast. When the dragon finishes barfing up poison sludge run to the opposite side and slash its arm with a dash attack and roll out of the way of its sweeping claw attack. Rinse and repeat. Eventually it will die.
The melee tactic is risky, since he can one shot you with a swipe of his claw if you are not blocking him and you need heavy armor in order to run through the poison without being stopped by it. The safest and relatively fast method is buying 35 firebombs from the Undead Merchant in the Undead Burg (only 50 souls per piece, so 1750 souls in total). Stand at the edge of the safe zone (where the purple poison stops hitting you) and throw firebombs at him. Just make sure to take babysteps back after each throw to stay out of the poison range.
There's also a ledge directly in front of the dragon which can be used for the firebomb strategy. Sprint and hug the right-hand wall after entering the dragon's cliff. You will climb up some rocks onto the ledge. From here, you can toss bombs at the dragon without any worry of him attacking you. Be sure to back up every couple tosses to make sure you don't fall off in front of him.
Magic Strategy: If magic is your forte, you are in luck. With soul spears and a little dodging this is a laughable boss. Attack it with your most powerful magic and get behind a barrier and block. Rinse and repeat. If you pass the dragon in the direction of New Londo Ruins it is possible to stay out of range while he continually vomits toxin. Spam magic/ranged with no fear of being attacked.
Faith Strategy: If you have ever been a part of the Sunlight Warrior Covenant, just throw about 6 Lightening Spears at it, and get your reward. If not, just revert to the melee stratagy, or go join the Sunlight covenant for the powerful Lightening Spears. This strategy is very effective because the Undead Dragon is weak to lightning.
Drake Sword Strategy: If you have obtained the drake sword from the Hell kite Dragon you can two hand it and spam the power attack without receiving damage from the Undead Dragon. There is an area on the dragons right side where it's toxic breath won't reach (close to the edge of the cliff) , spam the charge attack from a short distance away from it's right arm. Take note that using the drake swords power attack will drain its durability and you may need to run back to New Londo to repair it, the repair costs 600 souls.If done correctly you will emerge victorious without a scratch.