71 transmog appearances and 3 mount, pet or toy drops across 5 bosses.
Book of Binding WillHeld In Off-hand
Bracers of Impossible Strength×2Plate Wrist
Bracers of the Bronze Flight×2Cloth Wrist
Helm of the Nether Scion×2Mail Head
Legguards of the Emerald Brood×2Plate Legs
MalevolenceTwo-Hand
Pauldrons of the Great Ettin×2Plate Shoulder
Proto-Handler's Gauntlets×2Mail Hands
Robes of the Burning Acolyte×2Cloth Chest
Storm Rider's Boots×2Leather Feet
Blade of the Witching HourOne-Hand
Daybreaker Helm×2Plate Head
Dragonheart Piercer×2Ranged
Drape of the TwinsCloth Back
Fang of TwilightOne-Hand
Helm of Eldritch Authority×2Cloth Head
Waistguard of Hatred×2Mail Waist
Arion's Crown×2Mail Head
Dispersing Belt×2Leather Waist
Feludius' Mantle×2Mail Shoulder
Glaciated Helm×2Plate Head
Glittering EpidermisCloth Back
Gravitational Pull×2Plate Hands
Hydrolance Gloves×2Leather Hands
Scepter of IceHeld In Off-hand
Terrastra's Legguards×2Plate Legs
Treads of Liquid Ice×2Cloth Feet
Battleplate of the Apocalypse×2Plate Chest
Coil of Ten-Thousand Screams×2Mail Waist
Hands of the Twilight Council×2Cloth HandsHelm of Maddening Whispers×2Plate Head
Kilt of the Forgotten Battle×2Mail Legs
Membrane of C'Thun×2Leather Head
Shackles of the End of Days×2Plate Wrist
Shalug'doom, the Axe of UnmakingTwo-Hand
Treads of Hideous Transformation×2Leather Feet
Twilight's HammerOne-Hand
Uhn'agh Fash, the Darkest BetrayalOne-HandBelt of the Fallen BroodLeather WaistBindings of Bleak BetrayalPlate Wrist
Boots of Az'galadaMail Feet
Bracers of the Dark MotherCloth Wrist
Bracers of the Mat'redorPlate Wrist
Crown of the Twilight QueenCloth HeadNightmare Rider's BootsLeather Feet
Shroud of Endless GriefCloth Back
Twilight Scale LeggingsMail Legs
War-Torn CrushersPlate FeetSign in with Battle.net to see which of these appearances and collectibles you already have, and which of your characters can still loot each boss this reset.