Skull/Halo 3

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: In order to obtain any of the skulls, you cannot start the level from a mid-level "insertion point"—you MUST begin the level from the very beginning. You do not, however, have to finish the level after you hold the skull. You can save and quit after holding it, and it will be fully unlocked.'''

Iron
Level: Sierra 117

Directions: This skull is at the end of the level. It is located on the roof of the building to the left of the building where Sergeant Johnson is being held captive, if you're facing Johnson. Travel all the way over to the left side of the roof, and the skull is sitting on the ground 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, similar to Halo 2 on Legendary. On solo, it restarts the mission.

Point Multiplier: 3x

Black Eye
Level: Crow's Nest

Directions: It's 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 food appears on) lies the “drum solo of life”. You can gain access to the pipes a few different ways, one of the easiest however is to jump on the crate like thing, then jumping onto pipes from there.

Difficulty: Normal, Heroic, Legendary

Achievement Icon: Skull marked with a bruise under one eye. Difficulty: Normal, Heroic, Legendary

Achievement Icon: A skull marked with a swirl of fog

Effect: No motion sensor

Point Multiplier: 1.5x

Thunderstorm
Level: The Covenant

Directions: After you take command of one of the Hornet vehicles, fly towards the first 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 rank promotion, for example, Minor Grunts will become Major Grunts.

Point Multiplier: 1.5x

Tilt
Level: Cortana

Directions: In the circular room where Cortana says "You like games? So do I..." 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.
 * Note: If you try to get the skull on your second time through the room (after you start the chain reaction) it wont be there.

Difficulty: Normal, Heroic, Legendary

Achievement Icon:

Effect: Enemy resistances and weaknesses are greatly increased. Essentially, it creates a situation where you will more often have to use a battery weapon to take down shields and power armor, and then an ammo weapon to finish the opponent off, than just use one or the other to take them down.

Point Multiplier: 2x

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.

Point Multiplier: 2x

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.

Grunt Birthday Party
Level: Crow's Nest

Directions: After the first objective, en 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 don't fall off to the floor, look over the edge to see a small ledge a few feet below you. The ledge has a green arrow pointing towards the wall. 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), or you can try to slide onto it from the edge. Once there, the skull will be at the end in a room. To pick it up you have to press and hold the Right Bumper.

Difficulty: Normal, Heroic, Legendary

Appearance: A white skull with a lighted candle on the forehead.

Achievement Icon: No Achievement.

Effect: When killed by headshots, Grunts heads will explode into confetti, and children cheering will be heard.

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 (try to position the grav lift on the line above the second light spec up the ramp, and try try try again, reverting saves when you fail repeatedly. Alternately, try and get the Grav Lift so that it is half way on and then jump into the stream from below), and there you have it! -But if it's not there, you probably didn't make it to the top. Fall down and look up and you will see one more "level." An alternate method is to take one of the crates from the room before, roll it down the ramp up next to the platforms, and place the grav lift on top of the crate. This will get you just enough height to reach the top platform.

Difficulty: Normal, Heroic, Legendary

Achievement Icon: No Achievement

Effect: Explosive force increased

I Would Have Been Your Daddy
Level: The Covenant

Directions: After defeating the Scarabs and going inside, get to the location with all 7 Ring Holograms. Continue until after the cutscene in which the Arbiter kills Truth, and kill the Flood(make sure that the Flood music has stopped) before jumping through the ring holograms in a specific order. That order is as follows (1 is at the entrance, 7 is closest to Truth): Please note: If you activate any skulls, this will not be in your skull inventory. Also, campaign scoring must be off. If you go into the 4th section of the room, where Truth says "How could i have known the Parasite would follow?" on the way in, you will get a checkpoint (and Cortana will say "I'm a thief. But I keep what i steal.").

4 6 5 4 5 3 4

When you jump through the final halo, the rings will start flashing, and you will be awarded with the spawning of the “I Would Have Been Your Daddy” skull. When you pick it up, the rings will stop flashing, and remain brightly lit. It will be right next to the light bridge that brings you over to the Prophet of Truth. Also, take note of how the background music changes as you walk past each ring once you've held the skull.

There are three different ways to find the IWHBYD skull, depending on the selected difficulty. The following sequence works on Normal difficulty - 4654534.

Difficulty: Normal, Heroic, Legendary

Achievement Icon: No Achievement

Effect: New Dialogue in Game (One of the extra dialogue moments include: In the level, The Ark, when the Monitor is shot by a rogue grunt, he/she/it says "I just got bitch slapped!" in a very robotic voice.)

Bungie.Net

Video
Gold Skulls Locations 9WrXr4Aa3Bs

Silver Skulls 3/4 Locations roXCIh2Rz60&NR

Silver Skull IWHBYD Location LLOm7olquhk

Guide to all 13 Halo 3 Skulls XIE7I2OPgyA