The DE melee weapons list is frankly lackluster. many of the options are limited to a single type of model or at best a very small selection of our forces, with the majority of our squad leaders looking at a choice of power sword or agonizer (you choose the agonizer), and our HQs not really much better off.
This thread is for adding weapons to our general arsenal, not for squad specific ideas.
First up: The Torment Blade. A terror weapon, the torment blade is not designed to kill but instead to cripple the unfortunate foe in the most agonizing ways the twisted designer could concoct. Troops flee from the horrific screams of their comrades wounded by this weapon, while even the mightiest of foes might succumb to the pain and be unable to carry on the fight.
Torment Blade: Melee S User AP -1 Damage 1
Wounds non-vehicles on 4+ regardless of enemy toughness.
A unit that takes unsaved wounds from this weapon must make a Morale check in the Morale phase, even if it took no casualties, at a -1 penalty per wound this weapon inflicted. This does not affect vehicles, but it does affect characters and monsters. Models wounded but not slain by this weapon are removed as casualties from a failed morale check triggered by this weapon before other models in their unit.
Next on the list: Void Blade.
The Void Blade is a darklight weapon, a beam of pure unlight contained in a specialized field that sculpts it into a 3-foot-long blade. There is little this weapon cannot cut through handily, though unfortunately the nature of the technology makes the blade impossible to use with the normal deft skill the Dark Eldar are infamous for.
Void Blade: Range: Melee. Strength: 8. AP -4. Damage D3.
Attacks with this weapon are made at -1 to hit.
(Note: yes, I am suggesting a power fist equivalent which is basically a darklight lightsaber)