Note: This quest chain was removed from the game with patch 3.0 (WotLK expansion), since Onyxia no longer requires any attunement. These instructions can still be used in WoW Classic Era/vanilla (level 1-60) as Alliance to get the Drakefire Amulet and enter Onyxia’s lair.
- Go to Morgan’s Vigil in Burning Steppes (it’s where the Alliance flight path is) and accept “Dragonkin Menace” from Helendis Riverhorn. You must be level 48+ to accept it. The dragons you need to slay are all on the far east side of Burning Steppes.
- Go back to Helendis Riverhorn and turn in “Dragonkin Menace”, accept “The True Masters pt. 1“
- You need to deliver a letter to Magistrate Solomon in Redridge Mountains. Turn it in and accept “The True Masters pt. 2“
- Now deliver this letter to Highlord Bolvar Fordragon in Stormwind City. Accept “The True Masters pt. 3“.
- Speak with Lady Katrana Prestor (she’s right next to him), then turn it back in to Bolvar. Accept “The True Masters pt. 4“.
- Deliver the letter to Magistrate Solomon in Redridge Mountains. Accept “The True Masters pt. 5“
- Go back to Burning Steppes to Marshal Maxwell and turn it in. Accept “The True Masters pt. 6“.
- Go and speak to Ragged John in Burning Steppes, then go back to Marshal Maxwell and turn it in. Accept “Marshal Windsor“
- Go to Blackrock Depths (BRD), kill High Interrogator Gerstahn for the Prison Cell Key, go back a bit to Marshal Windsor and speak to him. Turn in “Marshal Windsor” and accept “Abandoned Hope“
- You need to go back to Marshal Maxwell in the Burning Steppes and turn in “Abandoned Hope”. He won’t give you a follow-up.
- Instead you have to go back to Blackrock Depths and kill mobs until A Crumpled Up Note drops. It can also drop from the mobs outside BRD in Blackrock Mountain. I had it drop from an Anvilrage Warden (elite) so you can solo this outside the dungeon if you want to. Right click on the note and accept the quest A Crumpled Up Note. Turn it in at Marshal Windsor in the cell in BRD. Accept “A Shred of Hope” from him.
- You now have to kill Golem Lord Argelmach inside BRD and loot Marshal Windsor’s Lost Information. You also need to kill General Angerforge in BRD and loot Marshal Windsor’s Lost Information. Then return to Marshal Windsor in his cell and deliver the two quest items.
- Accept “Jail Break!“, but before you do, clear the ring his cell is in (not the part where High Interrogator Gerstahn is), the open area you see straight ahead as you enter the dungeon, and the Halls of the Law which is the ring that goes around outside the arena. Then accept the “Jail Break!” escort quest. If you fail you have to reset the dungeon to reaccept the quest, as far as I know.
- Once you’re done, go back to Morgan’s Vigil in the Burning Steppes and turn it in to Marshal Maxwell. Accept “Stormwind Rendezvous” and fly to Stormwind City.
- Go out to the front gate and talk to Squire Rowe. He will summon Windsor. Turn in “Stormwind Rendezvous” and accept “The Great Masquerade“. Just follow him, stand back and let Bolvar do the fighting. Easily soloable, just don’t take aggro. Turn it in at Bolvar and accept “The Dragon’s Eye“
- You need to go to Haleh in Winterspring. You can run through the cave just east of where she stands and in the back there is a blue circle which teleports you to her. Bring a group or be prepared for multiple corpse runs if you do want to go through the cave. Turn in “The Dragon’s Eye” and accept “Drakefire Amulet“.
- This last step is the same for Horde and Alliance. You have to go to Upper Blackrock Spire (UBRS) and kill General Drakkisath and loot his Blood of the Black Dragon Champion. A raid of about 10 level 60s is a good idea for this part. Bring the blood to Haleh to complete “Drakefire Amulet” and get your amulet.
As for Onyxia’s Lair, it’s located in Dustwallow Marsh at 53.77. You need to wear the Drakefire Amulet or have it in your backpack, be in a raid and be at least level 50 to enter.
Onyxia’s Lair is at 53.77 in Dustwallow Marsh in Kalimdor. You can use an addon like Leatrix Maps to display coordinates.