Halo: Campaign Evolved - How To Unlock LASO Difficulty Guide

Published Jul 25, 2026, 1:02 PM EDT Nicholas Becher is a gaming journalist with an MFA in Creative Writing from FAU. With extensive experience playing video games, he covers all forms of gaming content at Screen Rant, from breaking news to the latest fan theories. Most-played games range from Clair Obscur to Civ to Elden Ring to Halo 2 and beyond. Halo: Campaign Evolved has a range of unique features that substantially improve upon the original experience in Halo: Combat Evolved from back in the day. For the most part, these updates are largely dependent on tracking down the various Skulls in the game, one of the two collectibles alongside Terminals. One unique aspect of Halo: Campaign Evolved is the ability to unlock a bona fide LASO difficulty setting, which stands for Legendary All Skulls On for the uninitiated. While LASO has been an unofficial difficulty setting for most Halo games in the past, there's never been a dedicated setting that you can actually enable before Halo: Campaign Evolved. That said, unlike the other difficulty settings in the game, it isn't available right off the bat, and you'll need to track down a number of specific Skulls in order to unlock it. How LASO Difficulty Works In Halo LASO, short for Legendary All Skulls On, is the ultimate challenge mode in Halo: Campaign Evolved. Unlike the standard Legendary difficulty, LASO combines the game's toughest setting with 17 mandatory skull modifiers that make each mission way harder. Before players can access the mode, they must first discover all 17 required skulls hidden throughout the campaign. Once unlocked, LASO becomes available in the Campaign and Campaign Remix menus. Every required skull remains active for the entire playthrough, meaning players must contend with modifiers such as shields only recharging after melee attacks, enemies with increased health and awareness, disabled motion trackers and auto-aim, reduced ammunition, tougher enemy ranks, and the Iron Skull, which restarts the level after death in solo play. Difficulty modifiers cannot be used if players want to earn the exclusive MYTHIC achievement or trophy for completing the campaign on LASO. While previous Halo games featured LASO as a community challenge or playlist, Halo: Campaign Evolved makes it an official unlockable game mode, and tying it to trophy unlocks means many players will feel compelled to give it a go. How To Unlock LASO Difficulty (All Required Skulls) As mentioned, there are 17 skulls required to unlock LASO, and finding them all means you'll have to play through all of the mainline Missions and Bonus Missions and track down the following Skull collectibles: Skull Effect Black Eye Shields only recharge after melee attacks on enemies. Boom Explosion radius is doubled. Eye Patch Disables all weapon auto-aim. Famine Enemy-dropped weapons contain half their normal ammunition. Fog Disables the Motion Tracker. Grunt Birthday Party Headshotting Grunts triggers a confetti explosion and cheering sound. Grunt Funeral Grunts explode in a blaze of plasma when they die. Iron Solo deaths restart the level; co-op deaths revert to the last checkpoint. IWHBYD Rare dialogue and voice lines occur more frequently. Johnny Ammo Seed Reloading discards any ammunition left in the current magazine. Malfunction After each respawn, a random HUD element disappears. Mythic Enemies have increased health. Pop Shooting Flood weak points causes them to explode. Speed Limit Sprint is disabled. Temperamental Allies become hostile much more quickly if you kill a friendly unit. That's Just... Wrong Enemies detect and react to the player more easily. Thunderstorm Upgrades the rank of most enemy units, making encounters significantly tougher. While many of the above Skulls are relatively simple to find throughout the campaign, others are a little more complicated and will require some commitment. For example, the Temperamental Skull is a Bonus Mission Skull with three separate requirements needed to unlock, taking down a "high-value target" enemy's shields in three separate locations during The Most Dangerous Game mission. To find all the Skull locations for the required LASO Skulls, check out our comprehensive Skull Guide here that links to each individual mission with specific details on each Skull. Mythic is another relatively tricky Skull to track down if you don't know where to look, and is found in a "secret area" during the Two Betrayals Mission. While there are plenty of Skulls to track down to unlock LASO, trophy hunters looking to unlock the MYTHIC trophy/achievement for Halo: Campaign Evolved have their work cut out for them once they've unlocked the mode. Halo: Campaign Evolved Systems 7/10 Released July 28, 2026 Developer(s) Halo Studios Publisher(s) Microsoft Studios Multiplayer Online Co-Op, Local Co-Op Cross-Platform Play Yes - all platforms Cross Save Yes - all platforms Franchise Halo