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This set is probably my favorite Transmog outfit I've used, because of the HUGE variety of pieces, no two of which come from the same set. There's some lowbie quest reward shoulders, a cloak from C'Thun, a Kalu'ak reputation chest, a belt from Shadowmoon Valley...this set is a mix of EVERYTHING.
It started (like usual) with the weapons. Falric's Wrist-Chopper is an intriguing mix of colors - black, steel, gold, white and icy blue. It took me a while to build the rest of the outfit, but every piece was chosen to complement and accentuate those axe colors. Even the yellow of Morgion's bones, and her icy blue glowing eyes (which I couldn't get to show in WoW Model Viewer, sadly) match the color scheme.
The regal colors, Falric's weapon, and Morgion's status as a Forsaken death knight all blended to give me a strange impression of a corrupted version of Lordaeron's royal blues and majestic golden lions...so much like Lordaeron and yet, so very clearly not.
The color focus was primarily on icy blue, with white as the secondary color - basically the tabard and cloak combined. The gold was important, but it had to be in small amounts - some gold trim here, a band of yellow there, yellowed fingers/toes, etc. Nothing overpowering, but I think it adds up to a strong color presence in the end.
Rarity - luckily for me, only a few pieces were hard to obtain, the headpiece and hands. I already had the helm, but I had to monitor the auction house for around two weeks before the hands showed. The rest were quest items or easily farmed. There are also no class-specific pieces, so any plate-wearer could build this set, if they wanted.
Head: Protectorate Headplate
Shoulders: Pauldrons of Zul'Farrak
Back: Shattershore Cloak or Cloak of the Devoured
Chest: Ivory-Reinforced Chestguard
Hands: Talonguard Gloves
Waist: Borak's Belt of Bravery
Legs: Replica Legplates of Heroism
Feet: Eternal Pathfinders
Tabard: Frostwolf Battle Tabard
Shirt: Blue Linen Shirt
Weapons: Falric's Wrist-Chopper