This is the last quest in Chapter 3 so make sure you’ve completed all of the side quests before embarking on this one. Leuvaarden will give you this quest once you’ve completed Lock and Key. He’ll tell you that they need some help in dealing with the Salamandra. You’ll have a choice now, either seek assistance from the Scoia’tael or from the Order of the Flaming Rose. The decision will depend on who you chose for Gold Rush.
If you’ve chosen the Scoia’tael path you’ll find Yaevinn at Golan Vivaldi’s house. For the Order you’ll find Siegfried at his post outside the cloister in the Temple District. Once they agree to join you in your fight go back and let Triss know. She’ll set up a meeting with everyone at the New Narakort Inn.
Finish up any remaining quests as you’ll be leaving this area for the next chapter. Then head to the New Narakort Inn. If you killed Vincent Meis earlier then his men will show up to attack you, along with a Salamanadra informant. If you spared Vincent he’ll show up as either a Werewolf or in human form (if you cured him). Either you you’ll have to battle through some Salamandra before heading upstairs.
As you’re preparing your grand plan with Triss you’ll be rudely interrupted by Roderick de Wett and some of the Knights of the Order. Triss will quickly teleport you out of there into the Salamandra Base.
Inside the Cave break your way through the roots with the Aard sign, kill the group of Salamanadra and meet up with your backup, either Siegfried or Yaevinn. After a quick chat with them head to the Portal and use it to call in more backup. They’ll help with the large battle ahead.
Once all of the Salamandra have been killed continue towards the back of the cave. Once again you’ll have a short chat with Azar Javed who ends the conversation by casting a spell at you. Luckily Triss cast Alzur’s Shield on you so the spell backfires and Alzur escapes through his own portal.
The Professor at this point will run away down the corridor. Follow him and defeat the creatures and try to kill the Professor. Once the Professor get’s knocked down a short cut-scene will play and then the two of you will drop down through the floor to the Kikimore Queen’s Lair.
Quickly run to the other end of the cave. The Queen will one-shot you so you’ll need to stay out of reach. Use the Aard sign on the archway to break the rocks and try to slow down the beast. Continue running down the corridor and breaking the archways as you go.
Once you get to the large chamber use the Aard sign once more on the supports and then run out the other side of the chamber. When the Kikimore Queen enters the chamber roof will collapse, killing the Queen.
Since the Queen ate the Professor once you loot the Queen you’ll find the Professor’s things inside as well. You should find the Professor’s Letter, Professor’s Report, The Book of the Wolverine, a Kikimore Queen’s Nerve and the Kikimore’s Ire Scroll.
Leave the cave to be confronted by Princess Adda and her guard. Triss will teleport you away just in time and you’ll end up on the Lakeside for Chapter 4.