Theory building: Support Drow

Drow needs a lot of levels to be useful: she really isn't the best choice as a trilane support, especially if roaming since she has no stuns and a terrible slow until level 5. Supporting in dual lanes is fine because of the free harass (remember Frost Arrows don't draw the creep aggro) and damage buff for ranged teammates, tri-laning is only decent to an extent: if you're playing with another good support that can zone out enemies, say Lich or Skywrath Mage, then it's fine, but pairing her with a ganker-kind of Hero like Shadow Demon or Vengeful Spirit is a waste unless they solo roam.

My build for a support Drow would probably be Power Treads into Blink Dagger: all her main skills are good supportive ones, but you would be wasting Marksmanship. the Blink Dagger allows you to split push without worrying about dying, since you will always be able to get away by Blinking into trees and TPing. This also lets you scale into a semi-carry role with relative ease.

Another possibility could be rushing a Morbid Mask after plain Boots, which allows you to farm ancient camps at level 6 and get some extra gold if there's enough space to farm.

Yeah, support Drow is legit. I think I've seen it once in pro play, but I can't remember how it worked out.

I think she's better as a roaming support than a lane support, popping into the lane for a kill and then heading somewhere else. With a bottle and the new rune system she would never have to go to the fountain. Problem is that she needs levels, so I would stick in lane AT LEAST until I had lvl 2 Frost Arrows.

Core would probably be Force Staff and an Urn of Shadows or perhaps a Medallion of Courage. Urn is the better fit on Drow, I think. And like I said, a Bottle is now really, really good for roaming supports. A survivability item with team benefits like Mekansm or Crimson Guard would also work, but there are obviously better heroes to hold it.

I'd probably only play her this way in a five-stack though, you'd get some funny looks lol.

Perfectly legit. I'vs done it a few times, and it worked.

Skill build is really the same as carry drow honestly, Frost Arrows maxed at level 7 for the permaslow, Gust maxed next, and precision aura last. I'd go 4/2/0/1 at level 7. Slow and silence are your best utility ; the aura is good but it's a late game skill, you just need 1 value point in early game.

Very strong lane presense for harassing and getting kills especially with the new 6.82 buff to the slow at low levels. Silence screws up offlaners with escape skills pretty hard which is always good.

Drow is still pretty level dependent so I think she's more of a dual lane support, not a trilane support. Or a roaming support after she gets a few levels but not immediately.

Only thing is, Drow is a position-dependent DPS hero no matter how you look at her. So you won't take your carry's farm in lane (just the XP), but you need to build positioning and cheap DPS and not utility. You can't provide your team with expensive utility items like Pipe of Insight, Scythe of Vyse, Necronomicon etc, if you want that you need another support like Keeper of the Light.

Instead I think build would be more like Force Staff, Medallion of Courage, Mask of Madness, Urn of Shadows or Mekansm, maybe Blink Dagger, and then go full DPS items and BKB once you get some farm going - you need to scale into late game.

Actually, I mention the possibility of a support Drow (although briefly) in my guide, and it certainly could be viable. My biggest issue would actually be deciding which ability to max first, as they all could certainly be used in a support setting. I don't know if it compares to having her in a carry role, but if you are stuck in a pub with 5 carries it will work very well.