Halo 3 skulls

Summary
A Skull in Halo 3 is an easter egg left in by Bungie to make the game more challenging or interesting, or to unlock potentials that would otherwise remain hidden. There is no information text to wield a skull, as there is with a weapon, but it can be picked up just the same, and its effects range from the useless to the terrifying. In Halo 2, these skulls were hidden very far out of the normal path of the level, sometimes even backwards. In Halo 3, it is the same old situation. In addition, the skulls now have some sort of importance to the Halo 3 Meta-game. They multiply the amount of points you receive in the meta-game, meaning that activating them in the lobby will give you point multipliers. -   Note:  Attaining all 13 skulls will unlock all of the Samurai armor in the Matchmaking section.

Iron
Level: Sierra 117

Directions: This skull is at end of the level. It is located behind the building where Sargent Johnson is being held captive, up on the roof. You can gain access to the roof on the far right side of the building. Travel all the way over to the left side of the roof, and the Skull isconcealed in the corner.

Difficulty: Normal, Heroic, Legendary

Achievement Icon: A skull marked with a stylized drawing of a hammer

Effect: When playing co-op, if either player dies the game restarts you at your last checkpoint. On solo, it restarts the mission.

Black Eye
Level: Crow's Nest

Directions: In the same room you start in. Hanging down from the ceiling is some piping. On top of this piping, on the side nearest to the large display (the one that Hood appears on) lies the “Black Eye Skull”. You can gain access to the pipes a few different ways.

Difficulty: Normal, Heroic, Legendary

Achievement Icon: Skull marked with one eye.

Effect: Your shield does not charge normally. To charge your shields you must kill something (enemy or ally) with a melee attack (anything but the Energy Sword). You can charge your shields into the Overshield range by doing this.

Tough Luck
Level: Tsavo Highway

Directions: At the point in the level when the huge covenant cruiser flies overhead, on your left is some large piping following the road you are walking on. Underneath this piping are some support beams that extend out over a cliff. Jump onto the first of these beams, and travel to the end of it. Look to your left, and the Tough Luck Skull will be sitting on a rock extending from a cliff edge.

Difficulty: Normal, Heroic, Legendary

Achievement Icon: A skull marked with a three-leaf clover

Effect: Enemies always make every saving throw, always berserk, always dive, never flee…

Catch
Level: The Storm

Directions: In the first area where you need to destroy the Wraith Tanks, when you enter this area, do not eliminate the Wraith Tanks (The skull appears when the tanks appear, and disappears when the tanks are destroyed). The Skull is located on top of the circular building next to the Anti-Air Tank. You can access the roof using a grenade jump, or jumping on the back of a hog.

Difficulty: Normal, Heroic, Legendary

Achievement Icon: Skull marked with a stylized drawing of a plasma grenade.

Effect: AI will toss more grenades.

Fog
Level: Floodgate

Directions: At the very beginning of the level, as you are walking down from the anti-air gun you destroyed in the previous mission, you encounter a ramp (next to a missile launcher). Around this ramp, you hit a checkpoint. At this point, you should also hear a marine yelling, “There! Over There!” You have a small window of opportunity at this point, but it is fairly easy to get the Fog Skull. Look up, and to the right, directly at the roof of the building next to the missile launcher. There is a single flood form (not to be mistaken with the two other flood forms jumping in front of you) which is holding the skull. Kill him before he jumps, and he will drop the skull down to the ground where you can retrieve it. Too early, and the skull will get stuck on the roof though, so just time it carefully.

Difficulty: Normal, Heroic, Legendary

Achievement Icon: A skull marked with a swirl of fog

Effect: No motion sensor

Famine
Level: The Ark

Directions: Near the point where the path you follow branches off into two sections (one leading to the area where you need to let the tanks across the bridge, and the other leading towards the area where you meet up with the frigate). Take the right path, as you would if you were completing the mission, and you’ll notice a structure above you / to the left of you (near the area where you encounter a few ghosts). You need to scale the rocks to the right of the structure, and then travel across it so that you pass 3 of the large support beams extending into the cliffs. Inside of the fourth support beam, lies the Famine Skull. A well placed grenade should have you up there in no time!

Difficulty: Normal, Heroic, Legendary

Achievement Icon: A skull marked with a skull

Effect: When enemies drop their weapons, they will have considerably less ammo in them.

Thunderstorm
Level: The Covenant

Directions: After you take command of one of the Hornet vehicles, fly towards the second force field generator (the one the Arbiter disabled), and land. The skull is waiting at the very top, at the end of the ramp extending over the sea.

Difficulty: Normal, Heroic, Legendary

Achievement Icon: A skull marked with a lightning bolt

Effect: Each enemy receives a field promotion and is upgraded to their next available level.

Tilt
Level: Cortana

Directions: In the circular room where Cortana mentions that she “Likes to play games too…” It’s a bit difficult to get to, as it requires getting on top of the ceiling of the room. Upon entering the room, head towards the left side where you will see some mushroom shaped extrusions along the wall. Get on top of these, and then look up and towards the right for another set of extrusions. Jump to these. From here, you should be able to jump on top of the ceiling of the room, where the Tilt Skull lies in the center.

Difficulty: Normal, Heroic, Legendary

Achievement Icon:

Effect: Enemy resistances are greatly increased. For example, the Brute power armor is normally pretty resistant to human weapons to begin with and fairly fragile against plasma shots. With Tilt turned on, the Brute armor is practically 100% resistant to any human projectiles and can only be taken down by plasma bursts.

Mythic
Level: Halo

Directions: At the beginning of the level start by heading into the canyon, but hug the right wall. Very soon, you will notice that there is a turn to the right that is off the normal trail. Head a bit down this path, and the “Mythic Skull” will be sitting there.

Difficulty: Normal, Heroic, Legendary

Achievement Icon: Skull marked with a swirl

Effect: Enemies have 2x more health and shielding, and are therefore harder to kill.

Blind
Level: Sierra 117

Directions: Near the first enemy encounter stay to the right. Follow the wall on around past the small building until you reach the cliff edge. The skull is on a rock right just over the edge.

Difficulty: Normal, Heroic, Legendary

Achievement Icon: No Achievement

Effect: HUD and first person arm disappear.

Cowbell
Level: The Ark

Directions: Begin by heading all the way to the part of the level where you battle the Scarab. After defeating it, look in the middle of the desert area which you battled it in for a fairly large structure (it’s the building you see if you are at the bottom of the ramp you are supposed to go up, and turn to look in the opposite direction). Inside of this structure are several Gravity Lifts (shown below). Take one of these for later. Next, head up the huge ramp, and head inside of the building (the one with the cartographer inside). Pass through a few of the rooms in this building, and you’ll eventually come to a room with a whole lot of Explosive crates. Right after this room is a Staircase/Hallway that leads to the level below. The Skull is located at the top of the room, at the point where you turn on the staircase to head for the next part of the slope. There are four platforms above you, the Skull is on the uppermost of these platforms. Use the Gravity Lift to jump up to it, and there you have it!

Difficulty: Normal, Heroic, Legendary

Achievement Icon: No Achievement

Effect: Explosive force increased

Grunt Birthday Party
Level: Crow's Nest

Directions: After the first objective, in route to the barracks, you will fall down into a large pipe. There will be smaller pipes coming from the sides and Drones (insect-like enemies) flying out right and left. At the end, look over the edge to see a small ledge a few feet below you. Your goal is to just drop over the edge and immediately pull back and land under the floor you were just standing on, (on the ledge). Once there, the skull will be at the end in a room.

Difficulty: Normal, Heroic, Legendary

Achievement Icon: No Achievement

Effect: When killed with headshots, Multi colored Confetti flies out of the Grunts head.

I Would Have Been Your Daddy
Level: The Covenant

Directions: Get to where Truth is dead and you've killed the Flood. Jump through the rings located by Truth in this order: 4 5 6 5 7 6 5 4 1 2 3 2 7 2 1 3 4 6 7 5 4 6 5 4 5 3 4. Make sure you do this after the cut scene with Truth's death, and after you've run through the long hallways with the rings above you clearning out all of the flood. The ring at the beginning is ring 1, and the one next to the energy bridge and Truth is 7. You will be awarded with " I Would Have Been Your Daddy" and the skull is located on the bridge to Truth.(not the full bridge, the narrower one near ring 7) You need to complete the level after you receive the skull. PS: The rings make sounds when you get near them... so do not expect them to make any extra tones when you jump through them. Also - once you have done it correctly the rings will all flash.

Difficulty: Normal, Heroic, Legendary

Achievement Icon: No Achievement

Effect: New Dialogue in Game

Background
While six of the skulls in Halo 3 have the same names as skulls in Halo 2, their effects may have been changed in some way, or as Bungie sees fit. For example, it is likely that the Mythic Skull still increases the difficulty of killing enemies, but it is not at all clear that it will do it in exactly the same ways as did Halo 2's Mythic Skull. Until Halo 3's release, little more can be said about the matter. Although it could be assumed that the Halo 2 names are actually placeholder names. The 6 new Halo 3 skulls are described on effect in the Bungie.net update of 9/25/2007 "Halo 3 How-to: Campaign Scoring 101" 

Video
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