What edition did GW introduce coven units to the Dark Eldar?

I'm interested in the special rules and stats grotesques, haemonculus and other coven units had prior to 5th edition. I saw some oldschool grotesques on ebay the other day. Were they always slow and tough? What codex edition was the earliest? I might pick up a used one on ebay.

3rd ed, but the models changed big time in 5th.

Back then, they weren't called Coven Units either. The were considered Dark Eldar. Find the box set if you can. They came in a box set against Black Templars

3rd ed was our first codex. There were no Wracks or Cronos back then.

Grotesques had no weapons or available upgrades. If they were not accompanied by a character they were subject to Stupidity (needed to pass a Ld test with their Ld 5 to move). They were T 3 with 2 Wounds, but were not effected by shooting attacks of less than S 6, though close combat worked normally (because you could "chop bits off them"). Opponents beaten by them in close combat had to fall back without a Ld test being taken.

Haemonculi didn't do much, since we didn't have Power from Pain back then, but they were cheap (25 points) and you could take 3 of them for a single HQ slot.

Talos had a gun that wasn't very good, (24", S 4, AP 5, Assault 6) that they had to shoot at the closest enemy models in range and line of sight, one shot per model, with any extra shots being wasted. They had an Attacks characteristic of D6.

Its worth noting that we did have Grotesques in 3rd, but not Wracks.
THe thing is, what we now call Wracks is what we used to call Grotesques. They were much smaller (probably the ones you saw on eBay) and ruleswise were as Calyptra describes above.
It was with the last 6th edition Codex that Grotesques became larger creatures, and we got new small things called Warcks.

5th edition codex is when they became big hulking monsters. Still remember when the model came out. Honestly, we have some of the best looking models.