After you encounter Philippa in the dungeons, you will have a choice to make. You can either save Triss from the Nilfgaardian camp, or you can help Philippa reach her house and remove the curse from Saskia. Before you make your decision, you may want to make note of the following information. However, it does contain a very mild spoiler, so for the sake of preserving the story, it will be behind a spoiled block. (Spoiler) If you choose not to save Triss, this will not actually lead to her death. She is being tortured in the camp, yes, and saving her may spare her some of that. Saving her will also lead to some interesting conversations that will give you more insight into Triss’ character. But even if you choose to help Philippa instead, Triss will not die. Instead, Letho will rescue her from the Nilfgaardian camp. Yes, this may seem odd right now, but trust that she will at least be safe up until the final encounter, when you will meet up with her again. (End Spoiler.)
This walkthrough will cover the continuation of the Where Is Triss Merigold quest, which will appear if you decide to pursue Triss instead of Saskia. From the area near the prison, behind the tower, you can reach the Nilfgaardian camp quite easily. Simply head to the right and walk down the short corridor to reach the entrance to the camp. It will be located to your left. When you reach this area, you will find Shilard speaking with the guards outside. They will see you, though, and quick action will be necessary. Take Shilard as you hostage and demand entrance into the camp. With Shilard as your human shield, proceed into the camp and begin to explore the entryway to the area. It won’t be long before an archer emerges and shoots Shilard, though. Even though he was a powerful man, Shilard was still disposable if it meant torturing Triss and finding out about the Lodge of Sorceresses.
You will now have a fight on your hands. Kill the soldiers who will run in from both sides. They shouldn’t be too hard to route. You will have to find an alternate path into the heart of the camp, as the streets will be crawling with soldiers out for your blood. Head over to the ladders to the side and climb them to the rooftops. Walk along the linear paths on the walls to reach the next area. Drop down to the courtyard with the pond below. More soldiers will run out when you do. Kill the soldiers quickly, and then proceed over to the climbable wall. Climb up the wall and speak with Renuald. He will tell you that Triss was plotting against the Kings and in fact was an enemy the entire time. This doesn’t exactly ring of the truth, though; Geralt has known Triss for a long time, and he won’t be able to see Triss plotting against him. More soldiers will stream in, and a fight against Renuald will ensue.
Boss Battle: Renuald
This battle will be long, and has the potential to get very annoying. If you find yourself having trouble with it, try going back a checkpoint and drinking some potions before you climb up the wall to buff yourself for the battle ahead. It’s not so difficult that it can’t be beaten without doing this, though, so play carefully and strike decisively to avoid having to go back to buff yourself. Renuald will be the most powerful of the enemies that you will be facing, so try to fend off the weaker soldiers first. Kill them by parrying their attacks or by rolling behind them and hitting them from behind. Use Quen to heal yourself, and Yrden to set traps for the enemies as they run about the arena. Even if you haven’t killed all of the soldiers yet, if you see Renuald get caught in one of your traps, rush over to him and wail on him with your sword. It may be enough to kill him before he can escape from the trap.
If you haven’t managed to trap Renuald during the initial scuffle, take care to avoid his attacks while you run about killing the lesser footsoldiers. Once the basic soldiers are dead, turn your focus to the knight’s captain. Renuald won’t have a ton of health, but he is strong enough to warrant dodging his attacks and timing your strikes carefully. Because this will primarily be a battle of swords, as Renuald is no magician, feel free to get in close and wait for him to strike. Parry his attacks to deal enough damage to kill him. If you find that you need an edge in the battle, cast Aard to take Renuald by surprise before going in for the kill.
After the long battle is over, Renuald will drop to the ground, dead. Loot his body to find a few highly useful items. The first of these is a key ring. This will contain the key needed to get into the dungeons where Triss is being held, as well as a few other keys leading into various rooms hidden about the camp. You will be able to loot some pretty decent items from some of these rooms, as well as a few alternative exits in case you are cornered, so keep this in mind when you pocket the keys, and when you are exploring and escaping the camp later. You will also find the Armor of Vicovaro on Renuald’s body. This armor is decently powered and has a chance of being the best armor that you have encountered so far, especially if you have not been diligent about completing side quests and crafting items from Diagrams. Loot it. Even if it’s not the best armor you have, it will sell for a pretty penny later. Finally, loot a letter from the Emperor to Renuald from the corpse. When you are ready to find Triss, head out to the other side of the area.