Looks like this is the wrong forum. This forum is not about BG3 but upcoming Divinity !
I guess the mods will move it, so I'll give some thoughts.
First, who is "the ancient one". No one is called like that, in the English version at least. Is it priestess Gut ?
Below is my most successful strategy to defeat the goblin camp.
Here's the strategy that has been most successful for me to take the goblin camp out. It seems to work every time, unless the dice are really against you.
Step 0 : To prepare for the big battle, I kill the guards with the worgs before the camp first. Usually gain their trust with illithid power, then position my troops and surprise attack them. After that's done, move to the friendly camp and assassinate the bugbears and goblins that you find outside upstairs after the "crumbling wall". You can do this without alerting the camp. There are 2 drunk goblins and 2 drunk bugbears that you can swiftly sneak attack and kill without alarming the camp. Finally, you can sneak up to the booyagh lookout on top of the tower, unseen, and backstab it without raising an alarm too. Without these 5, especially the booyagh lookout, your later battle in the courtyard will be easier.
Step 1 : Since I'm a total, unconditional Minthara fan, I need to save her. And I also want to save the tieflings. So the next step will be to go to the worg pens, free Halsin, and kill everyone in the room without letting them raise the alarm. I usually leave Shadowheart near the entrance to intercept and kill anyone trying to run out and alert the guards. I then tell Halsin to stay put and go to Minthara to reveal the Druid grove, so she will attack.
Step 2 : I betray Minthara and save the grove. This combat is the only one in the game where I use barrelmancy. Because it's Zevlor himself who set up that plan. So all barrels I collected and sent to camp during the game are now positioned in the attackers field to go boom. Since Minthara is stationed on the little hill, she will be safe from the conflagration. I positioned 2 or 3 of my warriors on the hill also to knock her out. The one that's left on thew wall would be Wyll, who can use misty step to go and help with subduing Minthy if needed. If not he'll help defend from above. The grove is saved and Halsin will appear and everyone's happy.
Step 3 : Now to go back to the hostile goblin camp, I 'll sneak to the main entrance over the bridge and surprise attack the goblins in the first courtyard. If you have AOE spells like fireball available, it will be fairly easy. But even on level 4 it can be done with clever manoeuvring and spell choice. However, don't move too far to the right so as to alert Crusher and his audience. When the first courtyard is empty, then you can go on and take out Crusher and the others.
Step 4 : Next one is priestess Gut. I go up the stairs from the courtyard and enter through the "crumbling wall" then surprise attack the goblins in the main hall from high up on the rafters. Try to take out or immobilize Gut first.
Step 5 ; Go to Dror Razlin's place. Once more, initiate via a surprise attack. Try to lure Razlin away from the room, so he's on his own. Be careful of the void bulbs that may throw you in the spider pits.
After Razglin is gone, it's just mopping up time.
