 Twilight Offering Bands#53491 · Armor | 251 | 80 | Wrists | Epic |
 Opal Runestone#4844 · Quest items | 1 | — | No equipment slot | Common |
 Opal Ring#11980 · Armor | 64 | 59 | Finger | Uncommon |
 Opaline Medallion#16623 · Armor | 57 | — | Neck | Uncommon |
 Opal Necklace of Impact#21766 · Armor | 50 | 45 | Neck | Rare |
 Opaque Eye of Zul#40178 · Gems | 80 | — | No equipment slot | Epic |
 Opaque Forest Emerald#40103 · Gems | 80 | — | No equipment slot | Rare |
 Opaque Dark Jade#39988 · Gems | 70 | — | No equipment slot | Uncommon |
 OOX-22/FE Distress Beacon#8705 · Quest items | 40 | 40 | No equipment slot | Uncommon |
| OOX-17/TN Distress Beacon#8623 · Quest items | 43 | 43 | No equipment slot | Uncommon |
| OOX-09/HL Distress Beacon#8704 · Quest items | 43 | 43 | No equipment slot | Uncommon |
 Onyx Shredder Plate#5755 · Armor | 35 | 30 | Chest | Uncommon |
 Onyx Ring#7547 · Armor | 46 | 41 | Finger | Uncommon |
 Onyx Ring#12001 · Armor | 50 | 45 | Finger | Uncommon |
 Ahn'kahar Onyx Neckguard#49989 · Armor | 264 | 80 | Neck | Epic |
| Ahn'kahar Onyx Neckguard#50647 · Armor | 277 | 80 | Neck | Epic |
 Onyxia Scale Cloak#15138 · Armor | 60 | 55 | Back | Rare |
 Onyxia Scale Breastplate#15141 · Armor | 62 | 57 | Chest | Epic |
 Head of Onyxia#18422 · Quest items | 60 | 60 | No equipment slot | Epic |
| Head of Onyxia#18423 · Quest items | 60 | 60 | No equipment slot | Epic |
 Onyx Grips#35903 · Armor | 138 | — | Hands | Uncommon |
 Onyx Choker#7548 · Armor | 46 | 41 | Neck | Uncommon |
| Onyx Choker#12032 · Armor | 48 | 43 | Neck | Uncommon |
 Onyx Idol#20867 · Quest items | 61 | — | No equipment slot | Rare |
 Onyx Claymore#3417 · Weapons | 26 | 21 | Two-hand | Rare |
 Overlord's Onyx Band#19912 · Armor | 68 | 60 | Finger | Rare |
 Onin's Report#7715 · Quest items | 1 | 1 | No equipment slot | Common |
 Omor's Unyielding Will#27464 · Armor | 115 | 70 | Neck | Rare |
 Omor's Hoof#23886 · Quest items | 0 | — | No equipment slot | Common |
 Omokk's Girth Restrainer#13959 · Armor | 60 | — | Waist | Rare |