You could additionally open the door next to Payde by talking to him, and once all the Magisters are aggroed run in and bring Windigo into the fight. If you do want to kill them, you can be sneaky about it and close the doors allowing you to pick off Waters and Siwan without the others noticing, then possibly take on Cadoc and Marel at once if you are feeling brave, before trying to take on the larger group in the main Holding area.

Once you are done with that, decide if you want to kill the magisters or not. So keep the important stuff in your own inventory, such as your backpack, resurrection scrolls, healing items, and perhaps most importantly at least one Bedroll. However, unlike the Early Access, NPCs do NOT retain everything you trade to them. Like starting armor, or weapons, or healing items. You can loot the areas you can get to including barrels and such to trade for things you do want. Except for Payde, do not talk to him yet. Regardless, you should start talking to the Magisters on the boat. I will not be including the personal quests of the Origin Characters in these sections but will make note of specific places where if you have an Origin Character on your team, you might need to be aware of certain things. You'll be collared which prevents Source Magic before your character even wakes up.

This is where you will start after Character Creation (Maybe not for undead or Fane, Unsure yet). You can read the original guide on the divinitiy original sin 2 steam community hub.

How to remove collar divinity 2