|Doing what it does best - delivering missiles.|
The Razorwing is a unique unit - being that it can move 36" at any time, and can also move 12" and fire every one of its sickening weapons. Two dark lances, a Splinter Rifle you can upgrade to a Cannon, and four missiles. The missiles it comes with are S6 AP5 48" Large Blast murder sticks. You can fire all four of them any time you want, which means four large blasts that are wounding most troops on 2s, and insta-killing T3 models. If you get a good spot, you can get around 7-8 hits with each template, and with BS4, they really don't go too far. Combined with the dark lances and the splinter cannon, you're looking at stacking an AWFUL LOT of wounds on a single unit, effectively giving you the opportunity to point your finger at a unit and gimping it for the rest of the game.
You ofcourse don't have to take the Dark Lances, as with most things in the book, you can trade them out for Disintegrators, for free. So you get 6 S5 AP2 shots you can lay out on the unit too, and if you're going for the maximum amount of hurt, it may just be better than two Dark Lances. I haven't done it, because honestly, I can never have enough Dark Lances. Once you shoot your load with it, I don't think Disintegrators would be nearly as useful as them. 5th edition requires you to have a load of anti-tank, since everyone is mech'd up. This is why in a lot of lists, people opt for Ravagers over the Razorwing, since it packs an extra Dark Lance, and is 35 points cheaper, leaving the massed anti-infantry fire for Warriors, or simply relying on a strong core of Wyches for dealing with enemy hordes. The codex gives you so many options, and it's a blast thinking of all of the things you can do in it. None of the armies I've been able to think of, no matter how min-maxed they are, seem like they aren't something the Dark Eldar would do.
One of the biggest surprised with the Razorwing is this - Closed top! That's right, it doesn't go down like SUCH a cheap whore to bolter fire. They stay at -2 to the chart, so it can't be wrecked nearly as easily as a normal Raider or Ravager(Though they'll need to shoot the back of it) can. With the addition of Night Shields, you really don't have to worry too much about getting rapid fired by many guns, which lets you worry about getting shot by lascannons more and getting auto-glanced. Flicker fields can only go so far, but for 10pt, they can really save your bacon. I shrugged off 6 penetrating hits with them once, and went on to bugger the hell out of armor since I still had my gunboat alive, instead of blown up 4 times. They're a must-have.
Ofcourse if you don't think four S6 missiles are enough, you can exchange some of them for a Necrotoxin missile, a poisoned 2+ pinning missile, or if you're a true weirdo, you can take the Shatterfield. A really strange S7 AP- missile that re-rolls to wound. Not quite as practical as the Necrotoxin, I think. To be honest though, you can leave them all as the stock Monoscythe and do just fine. It's 5pt for any replacement and you're looking at 20pt for a rack of custom missiles, when you come with four great ones anyway. Its cousin, the Voidraven, can take some truly horrifying missiles though, which I might go into some other time. It's not nearly as good as the Razorwing in my opinion though.
I'm making a 500pt list for the next tournament I'm going to. That's the next one up! If you've started to develop a fledgling interest in 40k, check out Lexicanum, and you can pop in words you don't understand. It's a community maintained 40k wiki, and they really keep it up to snuff. Great place to learn about it.