Complete the following tasks to unlock the corresponding bonus content for that level:

Allies and Bosses Art: Curse Of The West under the Shootist difficulty.
Attract Mode Movie: Dead Light Prism with at least 80 kills.
Cowboy Animatic: Torture Maze with at least 30 melee kills.
Darkwatch Archives: All Gunslinger levels on Deadeye.
Enemies 1: Boneyard with at least 65% accuracy.
Enemies 2: Showdown with at least 20 melee kills.
Environments 1: Darkwatch Outpost with no deaths.
Environments 2: Invasion under the Deadeye difficulty.
Environments 3: Curse Of The West in 10 minutes or less.
Evolution of Jericho: Single player campaign under any difficulty.
Highmoon Trailer: Rescue in 15 minutes or less.
Rescue Intro Movie: Hangtown with at least 20 headshots.
Showdown Animatic: The Right Train under the Shootist difficulty.
Vehicles: Deadfall with at least 20 headshots.
Weapons: Morning After with at least 70% accuracy.
Wrong Train Animatic: The Wrong Train with at least 65% accuracy.

Click the [Right Analog-stick] to activate your "blood" vision.

Be careful when fighting banshees. If you cut off their arms and they still live, they will fire non-stop energy balls at you.

When fighting Lazaurus for the final time, hide in the house when he is using his twister move. It will shield you. Also, when he shoots his fireballs and smoke clouds, shoot them. They will blow up and you will be unharmed.

Click the [Left Analog-stick] to duck.

Blood Frenzy: Adds a supernatural boost to hand-to-hand combat.

Turn: Turns some enemies against each other for a short period of time.

Black Shroud: Covers you in a black shroud of darkness that hurts enemies when they attack for a short time.

Soul Stealer: Sucks the souls right out of living enemies (can be used at a distance).

Immortal Friends: No matter how many times you shoot Cassidy or Tala, they will not die.
When you defeat Lazaurus, if you choose to break the spell of the west, in the final battle you will fight Tala in her vampire form. If you choose to become the new lord of vampires you will fight your ghost-friend Cassidy, when she is an angel, then kill Tala in the intermission sequence.

Silver Bullet: Unlimited and more powerful bullets for a short time.

Fear: Some enigmas will run scared for a short time.

Mystic Armor: Strong armor (possible 0 damage) for a short time.

Vindicator: Shoots a chain of lighting that instantly destroys most small monsters.

Press [Down] to switch to your second weapon slot. This is useful if you are saving a rail rocket or shotgun. Also, press [Up] to switch between dynamite and splitter grenades (if available).

When fighting a group of enigmas and there is a Dark Mark (Evil Tree), quickly go for the tree. Destroy it before fighting any enemies. When it is destroyed, it will shoot a shockwave, instantly destroying all enemies in that area.

Hold down the fire button [R1] on the pistol (Redeemer) to "fan" it, or shoot in rapid fire.