In order to open the locked door at ( 119, 1, -125 ) Copy/waypoint 119, 1, -125, you will need the Doomwing Key, which can be found at ( 137, 10, -133 ) Copy/waypoint 137, 10, -133. (I found the key at ( 134, 11, -132 ).
To distract Jin'tiz, pick up the vial of Volatile Fluid at ( 98, -27, 5 ) Copy/waypoint 98, -27, 5 and use it on the large egg at ( 126, -27, -13 ) Copy/waypoint 126, -27, -13. Jin'tiz will emote and they come flying over to the egg, allowing you to pick up the mutagenic potion without aggroing him.
Alternatively, you can cast Soothe on him. However this may fail and cause him to aggro. If he does aggro, make sure someone grabs the potion and let the group wipe.
Examine the Refined Mutagenic Potion to be offered the subquest Transmogrification. This sub-quest requires you to obtain a scale from the body of Doom Lord Septimus to refine the Refined Mutagenic Potion.
Kill Sothis and pick up the Torpor Draught on a table in his room at ( -9, -69, 291 ) Copy/waypoint -9, -69, 291.
Place the draught in the 'Bubbling Cauldron' that Katalkana, Steward of the Legion walks near to put him to sleep. ( -23, -68, 449 ) Copy/waypoint -23, -68, 449
Once Septimus is dead the Transmogrification subquest will update, and the person who has the quest must drink the Transmogrification Elixir that has been placed in their inventory.
Hail Watcher Ningiza, who will spawn nearby after a short delay. ( -108, -72, 444 ) Copy/waypoint -108.36, -71.77, 443.96
Speak with the three officers who you spared. One after the other, Doom Guard Vimock, Jin'tiz the Cataloguer, and Katalkana will come into the Rookery, lay a chest down, and be available for dialogue.
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