Below is how to acquire the Shadowknight only Darkforge pieces. Each Darkforge piece requires the corresponding decaying piece (ie: a Darkforge vambrace requires a decaying vambrace, and something else), which are only found on the Lizardman Crusader, in Cazic Thule. The Crusader is rumoured to be lvl 35ish Shadowknight (send that pet in first, to eat that 351 point Harm Touch) and supposedly drops a decaying peice about one out of ten times. Most of the Darkforge pieces require a left and right decaying component (ie: decaying left leg and decaying right leg to make Darkforge Greaves). Below is exactly what you need (beware, the npc you take the stuff to have a short life expectancy, ask those around you to let you talk to him before they kill him, also, be certain that any items that are stackable are NOT stacked when you give them away... ie: one item per slot):

The Undead Knight in Mistmoore's cemetery will make Darkforge Helm, Breasplate, Vambracers and Bracers:

• Darkforge Helm (13 ac, Int +5, +5 Sv All, 6.0 wgt): Decaying helm, decaying visor, 2 Freeport Militia helms (any of the guards inside the city drop them, roughly 50% of the time).
• Darkforge Breastplate (20 ac, Sta +10, +3 Sv Magic, 9.0 wgt): Decaying breasplate, decaying mail, two enchanted bars of platinum (not stacked!!!).
• Darkforge Vambraces (11 ac, Str +4, 5.0 wgt): Decaying vambracers (left and right), Qeynos kite shield (any Qeynos guard that has a shield).
• Darkforge Bracer (9 ac, Dex +3, 3.5 wgt): Decaying bracer, minotaur hero shackle (minotaur hero, in steamfont).

The Undead Knight in Drelzna's room of Najena will make Darkforge Gauntlets, Greaves and Boots:

• Darkforge Gauntlets (12 ac, Dex +2, +5 Sv Magic, 5.5 wgt): Decaying gauntlets (left and right), 1 bar of enchanted platinum.
• Darkforge Greeves (13 ac, Sta +9, +3 Sv Magic, 7.0 wgt): Decaying greeves (left and right), 2 melatite (MB and MC Model clockworks in sola).
• Darkforge Boots (11ac, Sta +3, 6.5 wgt): Decaying boots (left and right), 2 faerie dust (fairy's in lesser faydark, uncommon drop).