Red Dead Redemption -- Undead Nightmare Cheats & Codes

You can enter the following codes in the Cheats Menu under "Options." Enter the entire phrase given below to activate the cheat, punctuation included. Capitalization does not matter. Once a cheat is entered you may toggle them from a master list. If the cheat effect isn't made obvious by its title, we give a description of it in parenthesis below. Entering cheats disables saving and Trophies / Achievements! Finally, cheats can often be found in a box at the bottom of the newspapers you can read in towns.

* Invincibility - HE GIVES STRENGTH TO THE WEAK
* Infinite Dead Eye - I DON'T UNDERSTAND IMNFINITY
* Infinite Horse Stamina - MAKE HAY WHILE THE SUN SHINES
* Infinite Ammo - ABUNDANCE IS EVERYWHERE
* Money ($500) - THE ROOT OF ALL EVIL, WE THANK YOU!
* Horse - BEASTS AND MAN TOGETHER
* Diplomatic Immunity (Marshalls ignore crime) - I WISH I WORKED FOR UNCLE SAM
* Decrease Bounty - THEY SELL SOULS CHEAP HERE
* Gun Set 1 - IT'S MY CONSTITUTIONAL RIGHT
* Gun Set 2 (buffalo rifle, sawed-off shotgun, semi-auto pistol, Schofield revolver, Winchester repeater, and fire bottle x3) - I'M AN AMERICAN. I NEED GUNS
* Who? (Turn into a Nobody) - HUMILITY BEFORE THE LORD
* Old School (Sepia Filter) - THE OLD WAYS IS THE BEST WAYS
* Sharp Dressed Man (Unlock Gentleman's Suit) - DON'T YOU LOOK FINE AND DANDY
* Lewis and Clark (Unlock all areas) - YOU GOT YOURSELF A FINE PAIR OF EYES
* Jack Attack (Change John into Jack) - OH MY SON, MY BLESSED SON
* Man In Uniform (Unlock US Marshal, US Army and Bureau Uniforms) - I LOVE A MAN IN UNIFORM
* Good Guy (Get a good reputation) - IT AINT PRIDE. IT'S HONOR
* Gang Chic (Unlocks Treasure Hunter Ouftift) - YOU THINK YOU TOUGH, MISTER?
* Hic (Permanent "drunk" effect) - I'M DRUNK AS A SKUNK AND TWICE AS SMELLY
* Coach (Spawns a coach) - NOW WHO PUT THAT THERE?
* Famous (become instantly Famous) - I AM ONE OF THEM FAMOUS FELLAS

Additions by Ghostleh and CheatingJason
Unlockable: No Cost Item Building

If you beat Undead Nightmare with a 100% rating you'll be able to build Undead Bait, Boom Bait, Phosphorus Coating and Blunderbuss Ammo for free.
Hint: Undead Treasure Hunter Locations

To begin the Treasure Hunter quests you'll need to find your first map at a camp site outside of McFarlane ranch. It will appear randomly. You'll find the map inside a chest. After that, use the map and the descriptions below to find the treasure.

* Rank 1 -
* Rank 2 - go to Vente's Place near Lake Don Julio and easily make your way by the mountains to find this easy treasure.
* Rank 3 - Head to The Scratching Post, the camp where you meet the soldiers that give you the army uniform. Up the mountains, easy.
* Rank 4 - Head to Sepulcro graveyard in Mexico, just south of there are a pair of tress, head past them to reach another bunch, search the area.
* Rank 5 - Head to Casa Madrugada in Mexico, follow the map along the mountains and if you climb on foot on a cliffy part you'll find your treasure.


- Thanks Harry.