We haven't killed it yet, but this is what my group is doing:

2 Dread
2 Mines
2 Dread
2 Mines
Phase Push (1 Tank, badass SCH DPS)
3 West Defensive, (2 Immediately, 1 from Allagan Field target after debuff expires) Tank South Defensive
2 West Defensive, 1 Mines
3 West Defensive, (2 Immediately, 1 from Allagan Field target after debuff expires) Tank South Defensive

I might be incorrect on the last phase (honestly we haven't made it under 20% yet) in when the tank is going in as I don't honestly know what they're doing, but I know what the rest of the group is responsible for.