It's important to cap your STR and Attack, then put on as much DA as you can. It's not actually important to use Razed Ruins and I wouldn't recommend it. If you have it skilled, use an Axe instead of a GAxe. You will get more hits per monster and it'll be easier to cap STR.
Voracious Violet/Harvester/Demonic Lash would probably be the best Atma choices. You will want a healer to help you on WAR.