Skulls are one of the most enjoyable features in Halo: Combat Evolved Anniversary. They let you customize the campaign with gameplay modifiers that can make missions much harder, much funnier, or simply different from a normal playthrough. Some skulls increase enemy strength, while others change weapon behavior, remove your HUD, or add entertaining visual effects.
If you have already found a few skulls but cannot figure out how to turn them on, the process is quite simple. This guide explains exactly how to activate skulls in the campaign and how they work.
What Are Skulls?
Skulls are optional gameplay modifiers hidden throughout the campaign. Every skull has a unique effect that changes the way you experience the game. They are collectibles, meaning you must discover them before you can use them.
Some popular skull effects include:
- Stronger Covenant enemies
- Larger explosion radius
- No motion tracker
- Reduced weapon ammunition
- Shield regeneration only through melee attacks
- Funny Grunt death effects
- No HUD or weapon display
These modifiers can be combined to create entirely new challenges.
Do You Need To Find Skulls First?
Yes. You cannot activate a skull unless you have already collected it during the campaign.
Whenever you discover a skull, it becomes permanently unlocked for your profile. After that, you can enable or disable it before starting a mission whenever you want.
You only need to collect each skull once.
How To Activate Skulls
Once you have collected at least one skull, follow these steps:
- Open the Campaign menu.
- Choose New Game or replay a completed mission through Mission Select.
- Select your mission.
- Pick your preferred Rally Point if available.
- Choose the difficulty level.
- Open the Skulls menu before launching the mission.
- Turn on the skulls you want to use.
- Start the mission.
The selected modifiers will remain active throughout that mission until you disable them again.
If you continue from an existing save instead of starting a mission through Mission Select, the skull selection menu may not appear. Starting a fresh mission from the campaign menu is the easiest way to activate them.
Can You Use Multiple Skulls At Once?
Absolutely.
The game allows multiple skulls to be active simultaneously. Mixing different modifiers creates unique gameplay experiences.
For example, you could combine:
- Mythic for tougher enemies
- Famine for reduced ammunition
- Fog to remove the motion tracker
- Black Eye for shield regeneration through melee only
Using several skulls together greatly increases the difficulty and is popular among experienced Halo players.
Do Skulls Affect Achievements?
Many achievements are directly connected to skulls.
Examples include:
- Finding your first skull
- Collecting every skull
- Completing missions with multiple skulls enabled
- Finishing difficult challenge runs
- Completing Legendary All Skulls On (LASO)
If you enjoy earning achievements, collecting every skull is well worth the effort.
Tips Before Using Skulls
Some skulls make only small adjustments, while others completely transform the campaign. Keep these tips in mind:
- Start with one or two skulls before combining many.
- Read every skull description before enabling it.
- Save difficult combinations for later playthroughs.
- Practice on Heroic before attempting Legendary challenges.
- Experiment with different combinations to discover your favorites.
Some skull combinations are designed purely for fun, while others are intended to test even veteran Halo players.
Can Skulls Be Turned Off Later?
Yes.
Skulls are completely optional. Before starting another mission, simply reopen the skull selection menu and disable any modifiers you no longer want.
You can freely switch between normal gameplay and customized runs without losing your unlocked skull collection.
