Three people stay in the back to be teleported one or two person keep their portal open and two run past where atheon spawns over to the left there's a ledge :)$$$. By it there's a pillar for cover once atheon spawns get him as close to the ledge as you can cuz once the three in the back get teleported he freezes in place have the two people there wait to shoot him and throw everything they got at him once the three players come back get everyone shooting atheon over the edge.100% works