Finished it earlier today, actually isn't too bad. Here is my overview:
(tl;dr at the end)
Requirements:
Collect every skull
Start a new legendary run with all skulls (including bandana) active.
'Continuing' may turn off skulls, so always 'Load' your LASO save.
The first few levels up until you can get the scorpion gun are the hardest parts of the entire run. At the very start I recommend getting a plasma pistol and any weapon that can give headshots, a BR can be found in the starting room in a dumpster if you dont want to use the pistol. When you encounter a brute with a rocket launcher for the first time you will want to swap out your plasma pistol for it, I think its much more useful and can get enemies without direct line of sight. This should get you all the way up to the boss fight with Tremonius in mission 2.
For the Tremonius boss fight I lured him into the lower area and spammed grenades at him through the small entry hallways. this keeps him from being able to push on you and will eventually kill him. If he makes it past your grenades, just run to the other ramp leading down and do it again.
After beating Tremonius and making it to his outpost you'll want to go directly for the scorpion gun, this gun makes it absurdly easy (relatively speaking) to beat this game on LASO. I used it exclusively from this point on. Here's a link on how to get it:
https://www.windowscentral.com/halo-infinite-how-get-scorpio...In most cases you will have to jump to be able to fire the gun at something, or else it will most likely just blow up immediately. Luckily this gun cannot make you kill yourself, so its fine if this happens or if you use it right next to an enemy. The scorpion gun also does not allow you to melee or clamber, so carrying either a sword or rocket launcher as your secondary is your best bet, I opted for the rockets just in case an enemy started firing on me as I was going for a melee.
From here on out I played every fight that I could from a distance, sniping every enemy I could possibly see with the scorpion gun and not moving in until everything was killed (as far as I could tell). I recommend leaving leave one grunt, jackal, or skirmisher alive at the end of each fight to melee for your shields back, otherwise you may not get any checkpoints and end up reverting back quite far. This game doesn't care if you beat a boss or finished a level, it will send you right back to when you were last safe with full health. I also used the threat sensor a lot, this helps make sure you dont leave any stragglers that will kill you.
Also a word of caution, if you are outdoors fighting things and your objective requires you to clear out an area of enemies, the enemies must actually be killed for the mission to continue. The two most notable areas for this are when
Because of cowbell and the scorpion gun combo, enemies will fly away at the speed of sound, and sometimes they will still be alive. If they fly too far away they will despawn and not actually count as a kill to finish the objective. If you notice this happen (and it will happen) I recommend going back to your last checkpoint if possible. If you get a checkpoint after this happens to you, run a couple hundred meters from the objective then come back, everything will respawn and you can try again.
If the blind skull is making it very difficult you can get an idea of where its at by pointing at something close while the grapple is equipped. If you want a full-time solution put a small piece of painters tape or something right over the reticle, or use strings to mark out its location. I fought from a long enough distance that multiple tries to kill an enemy was fine 99% of the time, so I didn't bother.
I think that's everything there is to beating this game on LASO, it isn't too bad after the beginning as long as you are patient, I may add a video to this post down the road explaining this stuff a bit better.
tl;dr:
1)Up through Tremonius is the hardest part of the run, push through it and you'll be fine.
2)Get the Scorpion gun right after you beat Tremonius, use this for everything. (how-to link above)
3)Keep your distance and try to end every fight with full shields using a spared grunt/jackal/skirmisher
4)If a 'clear area of enemies' objective is stuck, revert checkpoint or run a couple hundred meters away and try again.