I'll take this case that you're playing in official server- no Over Enchanted weapons and armors.
You won't have abundant source of instant HP/MP bottles.
No insanely full buff NPCs.
So all the minion will be very hard to kill.
Then you'll need about 4 party to take her down.

These are facts that you should know about ant queen.

1. Ant Queen and all her minions are very weak to Fire attack.
2. Nurse ant heal like mad when ant queen got hit.
3. Nurse ant will abandon the Queen to aid the ant larva when beaten.
4. Even if the Larva HP goes to 0 it will not die.
5. some Minion will attack anyone attacking the ant larva. (they can still he attract by Hatr skills)
6. Queen Ant Larva room locate in the back of where the Queen stay.
7. Good luck << fact ??

knowing these facts you know that you should distract Nurse to damage the queen and kill all other minion to help tanker survive.

*** try not kill the Nurse since they'll respawn really fast close to AQ and begin to heal if they're too far away from Larva.

All player at LV 43 for the best drop chance, if possible put them all in one clan with High LV OL prebuff before the fight. - at this point OL will just stay out of the room and can no longer be used you must finish everything within 20 minutes.

1. AQ Tanker team consist of 1 Best tanker you can get / healer and rechager to tank the AQ.

2. DD team best to have a lot of Fire Mages but Rangers will do

3. DD party+with 1-3 healer to sneak into ant Larva room and pawn them like mad (tanker here use hate to distract soldier from DDs)

4. Tanker + Healer party for group 2 and 3 tanker here use hate to distract AQ minions from DDs.

Finally, share things up fairly so everyone get what they deserve.

4 parties???