I have been looking at the new Reborn Warhost detachment from the Fracture of Biel-Tan book some more and trying to come up with an army that maximizes the many options provided by this force structure.
A few things that jumps out to me, now that the various “Reborn” Eldar can mix and match from Eldar, Dark Eldar, and Harlequins as a single faction (i.e. they are the Ynnari faction now, and so lose Battle Focus/Power from Pain, but gain Strength from Death and the related ability to use “Soulburst” when a unit is destroyed within 7″ of one of their units) are the following:
 Wraithguard with attached Dark Eldar ICs and WWPs are very deadly, especially now that they can “chain” together bonus Shooting phases in a single turn via Soulburst, if they kill a unit outright when they arrive by Deep Strike (which they are almost guaranteed to do, given massed D weapons). Being able to Deep Strike with no scatter is in and of itself exceptionally potent, but when you combine that with T6/3+ save model who are all packing 12″ range D weapons, you have a squad that can basically “point and remove” enemy units at well, even if they are Deathstars, Super-Heavies, etc. I think Wraithguard squads combine particularly well with an attached Succubus with Archite Glaive and WWP, since the Ghost Warriors give the unit majority T6 (thus allowing it to soak up lots of small arms fire that would normally be a major threat to the Succubus) and the Wych HQ provides very potent close combat ability that the Wraithguard inherently lack (i.e. 5 x WS8 S4 AP2 attacks at I8 on the charge).
 Harlequin Troups have always been top-notch in melee, but in their stand-alone codex lacked the combination of mobility and mass (i.e. they could not take max size squads in their transport, since the Starweaver only carried up to 6 passengers) to get into combat reliably and you were usually limited to 3 or less Troups anyway, based on what Formation or detachment they were taking. Well, the Reborn Warhost solves both of these problems, allowing you to take up to 6 Troups if you desire and, for three of these squads, you can include 10 models and load them into Ynnari faction Dark Eldar Raiders from the Fast Attack slots, which gives you some target saturation and lots of mobility to get your Killer Clowns into close combat, where they belong. Finally, since Harlequin Troups did not have “Battle Focus” or “Power through Pain,” they lose nothing by becoming Ynnari faction and in fact gain the bonus of “Soulburst” abilities, which can make them go from strong to down-right devastating (i.e. imagine a Troup of 9 Harlequin players and attached Shadowseer moving up 6″ in their transport and disembarking 6″ , then the Shadowseer casts the “Word of the Phoenix” power from the new Revenant discipline, which allows them to Soulburst and get a “free” additional 6″ move, followed by a 2D6″ charge, with re-rolls from Fleet, giving them a charge threat range of between 20-30″ in a single turn, with an average charge threat range of 27″). Additionally, if the Harlequin Troup destroys an enemy unit in close combat, then it can use Soulburst to try and charge another nearby enemy unit in that same assault phase, which both keeps the Harlequins in combat (and clear of enemy shooting, which is very dangerous for them) and ties up/destroys another enemy unit altogether.
 At first the Yncarne is not an overwhelming powerful looking Lord of War choice, especially given its high points cost (40MBs) and somewhat limited abilities (i.e. no Shooting ability outside of Psychic Witchfires, a MC with only 6″ movement per turn, etc.). Where he really shines, though, is his ability to “teleport” with no scatter to any location where a unit (friend or foe) was just completely destroyed (he can do this all game long, as many times as he wants, and can even use it to come out of DS Reserve onto the table as early as Turn 1). Additionally, he has an aura which gives all friendly Ynnari forces within 12″ Fearless and FNP, which is a big deal, especially for some of the units I have mentioned above (i.e. Wraithguard, Succubii, and Harlequin Troups all benefit significantly from these buffs). Finally, while it cannot charge on the same turn that it “teleports” to the site of a unit that was just destroyed, on the subsequent turn it can charge and the Yncarne can put out some very significant damage with its multiple S6 AP2 Fleshbane/Armourbane attacks, all at very high WS and Initiative.
So, taking all of these things together, I think a competitive “Reborn Warhost” detachment could look something like this:
-2 x Succubus (each with Archite Glaive, WWP) — 260 points
-3 x Harlequin Troups (each with 9 members, all with Harlequin Caresses) — 681 points
-2 x Wraithguard Squads (each with 10 models with Wraithcannons) — 640 points
-3 x Raiders (each with Night Shields and Disintegrator Cannons) — 210 points
LORD OF WAR
-Yncarne — 200 points
This list comes in just under 2000 points (which is the level I almost always play at) and, while a little light on model count (i.e. 3 vehicles and 50 infantry), it has very solid mobility, decent durability, and above average hitting power in both close combat (Harlequins/Succubus/Yncarne) and shooting (20 Wraithcannons!). While I don’t think this would be an easy, “point and shoot” army, in the hands of a skilled commander I think it could be very dangerous.