Halo: Campaign Evolved Guide to All 42 Skulls

Halo: Campaign Evolved packs a total of 42 skulls across its missions and bonus missions, with up to three skulls per chapter. The game treats skulls as collect-once objectives—grab them and you don’t need to finish the mission to count the set. Beyond collection, unlocking different skulls enables special gameplay modifiers, and collecting all available skulls across the campaign can trigger multiple trophies/achievements (including “Craneal,” “Haciendo un collar,” “Cazarrecompensas,” and “Contenido de coleccionista” if terminals are also found).

Key takeaways

There are 42 skulls total, with up to 3 per each of the 13 missions.
Once a skull is picked up, it counts as obtained immediately—you don’t have to complete the mission.
Three bonus missions each contain 3 skulls, each with its own set of modifier effects and exact locations.
Unlocking skulls can trigger achievements/trophies such as “Craneal,” plus others tied to collection and terminals.
Three additional skulls are not tied to any map; they unlock automatically after obtaining any three skulls.

Bonus missions: where the first 9 skulls are hidden

Bonus Mission 1: “Boarding Action” includes these three skulls (in the order listed by the campaign path):

Avería (Gathering Point Alfa): when you respawn, a random element on your HUD will stop showing.
Árbol de munición de Johnny (Gathering Point Bravo): reloading causes you to lose the remaining ammo in the discarded magazine.
Líder (Gathering Point Charlie): headshots no longer deal bonus damage and won’t cause instant kills.

Bonus Mission 2: “The Most Dangerous Game” also has three skulls:

Temperamental (Gathering Points Alfa/Bravo/Charlie): if you kill an ally, teammates will attack you faster.
Recesión (Gathering Point Bravo): each shot consumes double the normal ammunition amount.
Ghost (Gathering Point Delta): enemies no longer react when hit by shots.

Bonus Mission 3: “Heavy Load” contains three more:

Parche en el ojo (Gathering Point Alfa): disables the aim assist/auto-aim feature on all weapons.
Fiesta de cumpleaños Grunt (Gathering Point Bravo): Grunt headshots trigger legendary celebration effects.
Eficaz (Gathering Point Charlie): enemies killed while you are at maximum health drop more ammunition.

Main campaign missions 1–10: skulls and what their modifiers do

Mission 1: “The Pillar of Autumn” (3 skulls):

Límite de velocidad (Gathering Point Alfa): disables sprinting.
Gran capacidad (Gathering Point Alfa): Assault Rifle magazine capacity becomes 60 rounds.
Perspectiva (Gathering Point Bravo): switches the player camera to third-person.

Mission 2: “Halo” (3 skulls):

Funeral Grunt (Gathering Point Charlie): Grunts die engulfed in plasma flames.
Dar y recibir (Gathering Point Charlie): firing consumes your shields, but damaging enemies restores them.
El suelo es lava (Gathering Point Charlie): you take continuous damage when you touch the “floor.”

Mission 3: “Truth and Reconciliation” (3 skulls):

Hierro (Gathering Point Alfa): in co-op, dying restarts you at your last checkpoint; dying solo restarts the level.
Especificación de resistencia (Gathering Point Bravo): UNSC vehicles cannot take damage.
Extranjero (Gathering Point Bravo): players can’t use weapons from other factions.

Mission 4: “Silent Cartographer” (3 skulls):

Pańuelo (Gathering Point Alfa): infinite ammo and grenades (and disables some trophies/achievements).
Acrofobia (Gathering Point Bravo): the “Cuerpo” now uses rifles and includes wings, enabling flight (also disables some trophies/achievements).
Disparo desde la cadera (Gathering Point Charlie): disables the zoom function on all weapons.

Mission 5: “Assault on the Control Room” (3 skulls):

IWHBYD (Gathering Point Bravo): triggers extra random dialogue, often absurd, from allies and enemies.
Enfadado (Gathering Point Charlie): enemies shoot faster and more frequently.
Cencerro (Gathering Point Echo): reduces the physical mass of objects, making them easier to move.

Mission 6: “343 Guilty Spark” (3 skulls):

Niebla (Gathering Point Alfa): disables the motion tracker.
Eso está… mal (Gathering Point Bravo): enemies become more aware of the player.
Han vuelto (Gathering Point Charlie): Flood combat forms reanimated by Infection Forms are more dangerous.

Mission 7: “The Library” (3 skulls):

Desequilibrada (Gathering Point Alfa): amplifies positive and negative damage multipliers (example given: plasma does more vs shields but less vs health).
POP (Explotar) (Gathering Point Bravo): shooting Flood weak points makes them explode.
Hambre (Gathering Point Charlie): weapons dropped by enemies contain half the usual ammunition.

Mission 8: “Two Betrayals” (3 skulls):

Mala suerte (Gathering Point Alfa): enemies always go berserk, constantly sidestep, and never flee.
Ojo morado (Gathering Point Charlie): shields only recharge when you attack enemies in melee.
Mítico (Gathering Point Charlie): enemies have more health.

Mission 9: “Keyes” (3 skulls):

Capturar (Gathering Point Alfa): requires playing on Heroic difficulty with no other skulls enabled; you must reach a grav-lift quickly, then pick up the skull shortly after it spawns near the top of the ship as it rises.
Ciego (Gathering Point Bravo): HUD and weapons are hidden from the screen.
Pińata (Gathering Point Charlie): melee hits on enemies make them drop inert grenades.

Mission 10: “The Maw” (3 skulls):

Recarga de reserva (Gathering Point Bravo): weapons keep reloading while they’re stored.
Boom (Gathering Point Bravo): explosion radius is multiplied by 2.
Tormenta eléctrica (Gathering Point Charlie): increases the range of most enemy attacks.

Three extra skulls that unlock automatically

In addition to the 39 mission skulls, the campaign includes 3 more skulls that aren’t found in any specific level. They unlock automatically after you obtain any three skulls, adding these modifiers:

Adaptación: randomizes which enemy factions appear in a mission.
Recargar: randomizes the weapons placed in the mission ahead of time.
Armisticio: enemy factions never fight each other.