Plus, on LASO the blast radius from rockets is higher as well, so any wall hit will cause an explosion that is bound to end your progress until your last checkpoint. The third wave has quite a few skimmers with rocket launchers (see above for why that’s a problem), Elites that are very precise when aiming their grenades and rifles, a Brute Chieftain, and a grunt mule that just happens to randomly pop up from behind a pillar and gift you a plasma charge. I recommend starting by focusing on the skimmers first, because those rockets are beyond annoying - you have to move quickly through the room, and will just hear the sound of a rocket whooshing by before you look back and lose your progress.