Holy Water

 is a weapon featured in the Undead Nightmare DLC pack.

Description
Holy Water is a flask of water that has been blessed by a religious official, thus making it holy and harmful to anything evil, including zombies. It is similar to the fire bottle, except that it kills zombies immediately, and they burn with holy blue fire rather than slowly burning to death with normal fire. It is acquired from Mother Superior on Marston's second mission in Mexico.

In the multiplayer mode, Undead Overrun, Holy Water is much different, as it acts like a kind of artillery designator. Once it is thrown, it immolates and incapacitates any Zombie nearby, as before. But soon afterwards, huge and explosive bolts of lightning fall from the sky randomly in the general area that the Holy Water landed. These bolts kill any zombies in the vicinity spectacularly and the bombardment itself is extremely destructive, including to the players themselves. Holy Water is one of the random weapon drops in Undead Overrun, and is also sometimes given to the player who opens the coffin in game.

An effective way to use Holy Water is to throw undead bait and wait until a few zombies come, and then throw the Holy Water. This tactic can also be used on Overrun when you are getting swarmed by the undead and it can help to complete the wave faster and earn a better combo.

Trivia

 * If thrown on a human, they will not be burned, but a blue flame still rises and they are injured.
 * Holy Water is supposedly the reason that when John Marston rose and became an undead, he still had his soul.
 * Sometimes, the player cannot whistle for their horse while wielding Holy Water.

Video
Holy Water can be seen in the following video: thumb|300px|left

Agua Bendita