Venom Blade

The Venom Blade is a favoured melee weapon of the ancient Drukhari nobility and was considered their hallmark. There are vast numbers of all kinds of poisoned weapons like vambrace blades, knives, daggers, swords, scimitars, whips and more, some of incredibly exotic design unimagined by humans.

These venom weapons each are host to thousands of micropores that constantly exude a distilled elixir of hypertoxins -- one of the most toxic substances in the galaxy -- that make the blade extremely lethal to any foe with just the slightest scratch.

Sources[]

Codex: Drukhari (8th Edition), pg. 111
Codex: Dark Eldar (7th Edition) (Digital Edition), "Armoury of the Dark City - Melee Weapons"
Codex: Dark Eldar (5th Edition), pp. 57, 60