Zed's Dead, Baby

Zed's Dead, Baby is an achievement/trophy in the Red Dead Redemption Undead Nightmare DLC pack.

Description
"Attain 100% Game Completion statistic in Undead Nightmare."

After obtaining 100% completion, unlimited item and ammo creation becomes available, making the ammo problems of the game almost virtually gone. This is only appliable to build ammunitions, not all types of ammunition.

Undead Nightmare is significantly easier to get 100% completion than Red Dead Redemption, and can easily be done in less than 9 hours total gameplay.

Acquisition
This achievement requires players to completely finish every aspect of the game, as detailed below. On June 25, 2011, Rockstar added a 100% tracker for Undead Nightmare to the Social Club website to help players monitor their progress towards each of these requirements.

Survivor missions

 * "Love in the Time of Plague"
 * "Curious Tales from Blackwater, USA"
 * "Get Back in that Hole, Partner"
 * "A Cure for Most of What Ails You"
 * "American Imperialism"
 * "Mother Superior Blues"
 * "A Civilized Man"
 * "On a Pale Horse"

Side-missions

 * "Birth of the Conservation Movement"
 * "Paternal Pride"
 * "Dinner for Two"
 * "Missing Souls"
 * "Filth and Other Entertainment"
 * "Biographies and Lies"

Have all the regions saved at least once:
West Elizabeth
 * Blackwater
 * Manzanita Post
 * Cochinay
 * Pacific Union R.R. Camp

New Austin
 * Thieves' Landing
 * MacFarlane's Ranch
 * Armadillo
 * Twin Rocks
 * Fort Mercer
 * Plainview
 * Ridgewood Farm
 * Rathskeller Fork
 * Gaptooth Breach

Nuevo Paraiso
 * Nosalida
 * Escalera
 * Tesoro Azul
 * Chuparosa
 * Las Hermanas
 * Agave Viejo
 * Casa Madrugada
 * El Presidio
 * El Matadero
 * Torquemada

Cleanse All the Graveyards:

 * 1) Blackwater Graveyard
 * 2) Coot's Chapel
 * 3) Odd Fellow's Rest
 * 4) Tumbleweed Graveyard
 * 5) Sepulcro

Save all Missing Persons
1% each for a total of 16%
 * 10 Missing Persons in Fort Mercer
 * 6 Missing Persons in El Presidio

Finding and breaking the Unicorn

 * To find and break the Unicorn, you must first find and kill the Chupacabra. You can only kill Chupacabra if you are a Rank 4 in Undead Hunter challange and it can be commonly found in Diez Coronas. After the Chupacabra is killed, it is common that the Unicorn will spawn in the fields north-west of Torquemada.
 * Look for an area on the map with three horses. The unicorn spawns in that area.

Complete all the Challenges:

 * Four Horses of the Apocalypse
 * Undead Hunter Challenges
 * Undead Treasure Hunter
 * Undead Sharpshooter

Obtain all the Outfits

 * Legend of the Apocalypse/Undead
 * Undead Hunter/Army of the Undead
 * Undead Cowboy Outfit

Trivia

 * The title of this achievement/trophy is a partial quote from Butch Coolidge, a character played by Bruce Willis in the film Pulp Fiction.
 * Upon reception of this achievement/trophy, builds no longer require items.