At Its Core - Belira Blastil
This quest is the third partisan quest given to you by Belira Blastil and it requies you complete What's Cooking and Furnace Fire in order to accept it. This task is similar to the previous one with how easy it is to complete.
Request Phrase: deal with
Task Type: Solo
1. Deliver 3 Energy Cores to Tinzenwen Geargoggler
2. Defeat 4 a lunatic rotoworks northeast of Tinzenwen outside
3. Speak with Tinzenwen
4. Speak with Belira Blastil
The very first thing you'll need to do is travel all the way back up to the top of the mountain and hand the Energy Cores to Tinzenwen. After you do that speak with Tinzenwen and he'll tell you that he wants you to stop all of the loud banging that you hear.
Note: If you have not already then I strongly recommend dropping a campfire at Tinzenmen as it'll save you a lot of travel time in the near future.
You'll notice that while you're in this area there is an emote too, "The walls of the room reverberate with clangs and bongs". The enemy that you need to defeat for a task update is the "a lunatic rotowork" which is found just northeast of Tinzenmen outside flying around. You shouldn't have that much trouble finding them, a picture of what you're looking for is shown below.
Defeat 4 of these enemies then return to Tinzenmen and speak with him again. Then you'll need to travel back to Belira Blastil which will complete the quest - that's all there is to it! All that's left from Belira Blastil is one more quest called Unscheduled Repairs and a HA called Ironing out the Legion.