City of Dalaran

Where: Dalaran, Alterac Mountains. You enter through the sewers, then pick among several paths up top (Blizzard).
Horde warning: Blizzard's 16 Oct note: Horde are attacked on sight in Dalaran's open world, and the key chain no longer opens the city to us. The dungeon is still open.
Arcane users: Wowhead says almost every mob here is immune to Arcane damage !.

Sewer key chain (Horde, Tarren Mill)

1. Prison Break In + Key to the City: Magus Wordeen Voidglare, Tarren Mill
2. Dalaran Patrols: same NPC
3. Blood in the Streets: same NPC
4. Heart of Disruption: Image of Archmage Modera outside Dalaran (Icy Veins puts her at 68.6, 45.2 on the Silverpine map). Gives the Dalaran Sewer Key; loot the Arcane Mote from the Shade of the Archmage

One key holder opens the gate for the group. Wowhead: swim over from Silverpine; it is a few minutes on foot from The Sepulcher.

Also grab

• The Grave Knight: Melisara, Tarren Mill (kill Atrexis)
• Source of Power: Doctor Martin Felben, Undercity Apothecarium
• Opportunistic Education: Rexxie Copperclutch, at the dungeon start

Bosses

• Atrexis the Grave Knight: Disarm, summons skeletons. Watch threat.
• Lyn the Ignored (bonus): Black Tome from Arugal's table in SFK, then use it beside the Ambermill Leyline Focus (Ambermill, Silverpine) to make the Tome of Dalaran. Use that on the purple rune in a side tunnel of the sewers. Shadow Bolt Volley you cannot interrupt, Curse of Thorns (decurse), skeletons.
• Arcane Anomaly: Focal Blast sends an arcane cutter round the room, do not get caught; interrupt Arcane Bolt on the tank.
• Mana Devourer: Debilitate keeps draining 200 mana from the whole group, so it is a race. Drain Vitality on the tank.
• Fel Ancient: Entangle roots two people, Fel Timbers drops poison pools. Do not stand rooted in a pool.
• Unstable Sentinel: kill the Angry Tomes first. Malfunction hits everyone within 25 yards; melee run out.
• Arcanic Enigma: kill the two Mana Phantoms (mana burn) first. AoE silence near him, dispel Manamorph, cleave the manalings.
• Shade of the Archmage: Arcane Bolt, Arcane Explosion, dodge Bounding Mana. Out of mana he Mass Polymorphs the group and Evocates.

Drops (both guides agree)

• Atrexis: Graveweave Bindings (cloth), Bonebinder's Signet, Gravespike Repeater (crossbow)
• Lyn: Cartilage Shapers (leather), Tendonscraper Dagger (spell), Bonepile Gaze (str shield)
• Anomaly: Ephemeral Grips (cloth), Mana-Warped Chain Shirt (mail), Runemender's Seal (healer ring)
• Fel Ancient: Blightleaf Rope (cloth), Garb of Fallen Felbark (leather), Felbough Arm (agi polearm)
• Sentinel: Unstable Crystalline Shoulderpads (leather), Refractory Scaleguards (mail), Blueprint: Spinning Wheel (Tailoring)
• Devourer: Slitherwrap Girdle (leather), Manascale Treads (mail), Spine of the Devourer (spell staff)
• Enigma: Violet Sorcerer's Robes (cloth), Drape of Shifting Energy, Wand of Mana Concentration
• Shade: Violet Sorcerer's Mantle (cloth), Archmagister's Faceted Pendant, Ponderous Orb (healer off-hand), Blueprint: Arcane Salvager (Enchanting)

Legacy: required for the 26-45 point (beta client data).

Sources Blizzard · Dev notes · Icy Veins guide · Icy Veins quests · Wowhead · Client data