To activate Skulls in Halo Campaign Evolved, select a mission and rally point, continue to the Select Skulls screen, and enable the modifiers you want before starting the level.
Skulls cannot be activated while you are already playing a mission. You must return to the campaign menus and launch the level again with your chosen modifiers enabled.
How to Turn on Skulls in Halo: Campaign Evolved
Follow these steps to activate a collected Skull:
- Open the Campaign menu.
- Select the campaign mode you want to play.
- Choose a mission and available rally point.
- Continue until you reach the Select Skulls screen.
- Select each Skull you want to activate.
- Confirm your choices and start the mission.
Only Skulls you have already collected or unlocked will appear as available options. Any Skull you have not found will remain locked.
Halo: Campaign Evolved contains 39 collectible Skulls across its 13 missions. Our complete Halo: Campaign Evolved Skull locations guide explains where to find all three in each level.
Can You Activate Skulls During a Mission?
You cannot switch Skulls on or off during an active mission. They are pre-launch modifiers applied when the level begins.
To change your active Skulls, leave the current mission and return to Mission Select. Choose the level again, adjust the options on the Select Skulls screen, and restart.
Because this replaces your active mid-mission checkpoint, it is usually better to finish your current level before experimenting with different modifiers.
How to Turn off Skulls
Return to the Select Skulls screen and deselect any modifiers you no longer want active.
Starting another mission without selecting a Skull prevents its effect from carrying into the new level. Collecting a Skull does not automatically activate it during normal campaign missions.
Campaign Remix works differently because three specific modifiers remain active throughout the mode.
How Skulls Work in Campaign Remix
Campaign Remix unlocks after you collect any three hidden Skulls. They do not need to come from the same mission.
Unlocking Campaign Remix also adds three more Skulls to your collection:
- Adaptation
- Armistice
- Reload
These three modifiers are always active during Campaign Remix and cannot be disabled. Adaptation changes which enemy factions appear, Reload randomizes placed weapons, and Armistice makes hostile factions ignore one another and focus on the player.
After selecting a Campaign Remix mission and rally point, you can manually add more collected Skulls or use Remix Selection to activate a random assortment.
Can You Use Skulls in Co-op?
Skulls work in online and split-screen co-op. However, the Fireteam leader’s campaign progress determines which missions and Skulls are available during the session.
Joining a player with more Skull progress may give the Fireteam access to modifiers you have not personally collected. Joining someone with fewer unlocked Skulls can limit the available selection, even when other players have found more.
Collecting a Skull during co-op permanently unlocks it for eligible Fireteam members who do not already have it.
Do Skulls Affect Achievements?
Some achievements require specific Skulls to be active. Others prevent difficulty modifier presets but still allow normal Skull settings.
Always check an achievement’s exact requirements before starting a long run. LASO and challenges such as Like Old Times require specific Skull combinations, while regular collectible achievements are not blocked by activating modifiers.
Skulls are not required for every unusual challenge. Our This is My Ship Now achievement guide explains how to handle Captain Keyes and his six Marines aboard the Pillar of Autumn.
