campaign guide | Updated July 30, 2026
Halo: Campaign Evolved LASO Preparation
LASO is a high-difficulty campaign challenge built around Legendary difficulty and Skull modifiers.
Verify your 42-Skull collection, test modifier interactions, choose a stable fireteam leader, and preserve a separate run before committing to a full LASO attempt.
Run a pre-flight check
Do not discover modifier interactions halfway through a long run. Test the intended Skull set in a short encounter first.
- Confirm Legendary difficulty in the lobby.
- Review every enabled Skull and its in-game description.
- Check that the intended fireteam leader has the required Skulls available.
- Use a dedicated campaign state for the attempt.
- Agree on restart, pause, and disconnect rules before launch.
Choose the leader carefully
The leader's campaign progress controls available missions, rally points, and Skulls. Use the player with the most complete and stable progression record as leader.
Make co-op repeatable
Keep the same group, platform updates, and communication setup where possible. Mid-mission checkpoints do not sync as cross-progression, so end sessions at reliable mission or rally-point boundaries.
- Verify all clients are updated before each session.
- Record the current mission and rally point.
- Avoid changing leader mid-run unless access requires it.
- Stop after a durable progression point rather than during a temporary checkpoint.
Separate challenge from verification
If an achievement or progression event does not register, collect the platform, Gamertag, enabled Skulls, mission, and completion time before replaying. Check release notes and official support for known issues.
Frequently asked questions
What does LASO involve?
It is a Legendary-difficulty campaign challenge using Skull modifiers.
Whose Skulls are available in co-op?
The fireteam leader's campaign progress controls the available Skull set.
Do mid-mission checkpoints sync to another platform?
No. Halo Support says mid-mission checkpoints do not sync.