Undead Dragon

Undead Dragons are a type of enemy found in the Valley of the Drakes, the Painted World of Ariamis, and (in a sense) Lost Izalith.

Overview
Undead Dragons are actually two different segments of what was once a living dragon. The top half can be seen without the bottom half only in the Valley of the Drakes, while both halves can only be seen together in the Painted World of Ariamis. Numerous bottom halves can be located in the largest lava lake in Lost Izalith.

The top half will spew a liquid substance in the general direction of the player, and will occasionally attempt to swat at or bite the player for damage. Fortunately Undead Dragons are very slow, immobile, and their attacks are telegraphed well in advance. The bottom half will attempt to trample the player, which can lead to a very rapid death.

Strategies
The undead dragon in the Valley of the Drakes can be safely dispatched at a range with pyromancies, sorceries, or arrows. It is even possible to kill it with melee attacks with good timing, although this is much more dangerous. Given that the dragon is guarding the dragon crest shield and the straight sword of astora, it is well worth the effort to put it down.

The second undead dragon blocks the way to Priscilla the Crossbreed at the Painted World of Ariamis. Similar strategies may be used here to kill it.

The dragon bottom halves populate Lost Izalith, and are in close proximity to each other, making them dangerous to kill. However, they deal friendly damage to each other, so aggroing each of them with an arrow or two will cause them to stomp each other to death in their attempts to reach you.