Continuing with our look at how the new Deathwatch army can effectively deal with competitive Xenos forces, here is my take on how to build effective Deathwatch Battle Groups to combat the Necron Empire:
 Wraiths with Whip Coils that are part of the “Canoptyk Harvest” formation — Again, this is one of the classic “power units” that you can expect to face in a tournament Necron army. Right out of the box, Canoptyk Wraiths are already very potent units, being Fearless Beasts with S6 T5 and Rending for all their close combat attacks. On top of this, they can be taken in squads of 3-6, come with 2W a piece, have a built-in 3++ save, and with the Whip Coil upgrade strike at I5 in close combat. Not bad for 43 points per/model! What really puts them over the top, however, is when they are included in the “Canoptyk Harvest” formation and, using the Adaptive Subroutines rule, they can gain Reanimation Protocols for each friendly Movement phase that they start within 12″ of the formation’s Tomb Spyder. This gives them a 33% increase in survivability on top of their T5, 2W, and 3++ (which can be increased to 50% if they are taken as part of a Decurion or have a nearby Illuminor Szeras). Taken all together, this makes for super tough unit that is very fast and dangerous in assault, which means it is a real threat to any army, and particular to a Deathwatch force with its “elite” make-up and typically low model count. Below is my best take on how to deal with Canoptyk Harvest Waiths —
EAGLE BOW Battle Group configuration:
-Two Aquila Kill Teams, each with two Terminators (both with CMLs) and eight Veterans (all with Stalker Boltguns and Bolters).
The key here for the EAGLE BOW Kill Teams is to use their superior range/firepower to defeat the Wraiths at long range, before they can close the distance and get into assault. Starting turn 1, I would have both squads engage the Tomb Spyder at maximum range with their 8 x S8 AP3 Krak missiles (with re-rolls of 1s to Hit using Malleus Mission Tactics and 1s to Wound from Aquila Doctrine), which should reliable kill that Monstrous Creature in a single shooting phase (even with 4+ Reanimation Protocols). This removes any Reanimation Protocols from the Wraiths, making them MUCH easier to bring down in subsequent shooting phases. Turn 2, the Wraiths should still be moving up to try and charge, so you can engage them with the full firepower of both squads using their CMLs and Stalker Boltguns. With Venator Mission Tactics and Aquila Doctrine activated (for re-rolls of 1s to Hit and to Wound against the Wraiths), these two squads put out 8 x Krak Missiles and 32 x Stalker Boltgun shots with Hellfire rounds (so, wounding on a 2+). On average, this results in 31-32 hits, 30-31 wounds, and 10-11 Unsaved Wounds after the Wraiths’ 3++ saves, which nets about 5 dead Wraiths out of a max squad size of 6. Even if the surviving Wraith manages to subsequently charge one of the squads in the EAGLE BOW Battle Group, Overwatch should net about 1 Unsaved Wound, meaning that the PFs on the Terminators ought to be able to finish the last wound on the Wraith off in combat reliable (especially with re-rolls of 1s to Wound from Aquila Doctrine). While the EAGLE BOW Battle Group is quite pricy points-wise, the ability to reliable kill of a Canoptyk Harvest (minus Scarabs, which are relatively easy to deal with) at range is very powerful and, fortunately, can translate effectively against other Necron units or even other armies as well.
 Triarch Stalkers — While these Necron Walkers are not exceptional combatants in their own right, with only 3 S7 AP- attacks in combat and a single Heat Ray for shooting, they bring A LOT to any competitive Necron army via their Targeting Relay rule, which grants +1BS to friendly Necron non-vehicle units within 6″. On top of this, they tough to bring down, with 3HP, AV13 on their front and side (as long as Quantum Shielding is up), and the Living Metal special rule. Efficiently eliminating any Triarch Stalkers, somewhat like dealing with Tau Pathfinders or Eldar Farseers, can be key for forces seeking to “de-synergize” their Necron opponents. Here is my take on the Deathwatch can assassinate Triarch Stalkers —
PALADIN DRAKE Battle Group configuration:
-Dominatus Kill Team with two Vanguard Vets (both with PF/LC), two Terminators (both with SB and PF/auxiliary Meltagun), and five Veterans (all with Meltaguns and Storm Shields).
The idea here is to use the Black Spear Strike Force “Sudden Onslaught” special rule to Deep Strike right next to the target Triarch Stalker(s) and light them up with 8 melta shots (with re-rolls of 1s to Hit with Dominatus Mission Tactics and re-rolls to Penetrate from Dominatus Doctrine), which should easily strip Quantum Shielding and kill even an entire squadron of 3 Triarch Stalkers. The Terminators can tank any non-AP2/1 firepower for the squad and the Vets can use their Stormshields to absorb AP2/1 attacks after this, so the squad is not on a complete “suicide” mission. In subsequent turns, the squad can shoot its Meltaguns again and then charge with 14 x PF attacks (or 8 LC attacks and 6 PF attacks), making it a significant threat to any Necron units that had previously been positioned near the Triarch Stalkers to take advantage of their Targeting Relay rule, be it a giant phalanx of Necron Warriors, Heavy Destroyers, or even Death Mark snipers. While the PALADIN DRAKE Battle Group is a more specialized build than some of the other Battle Groups I have proposed, against any army that relies on Elite infantry or heavily armored vehicles, I think it can be the Deathwatch’s more durable and more versatile version of Eldar fire Dragon squads.
 Doom Scythe — While perhaps not as notorious as Canoptyk Wraiths or event the Triarch Stalker, the Doom Scythe is a very potent Necron Heavy Support Flyer that presents a very significant threat against Deathwatch forces because of its S10 AP1 Small Blast Death Ray and multi-shot TLed Tesla Destructor, both of which can inflict multiple casualties on Deathwatch units every Shooting Phase. While the Corvus Blackstar (with the Blackstar Rocket Launcher) might seem to be the “natural” counter to Doom Scythes, I think actually the following Battle Group might be a more efficient defense against this Xenos threat —
IRON PIKE Battle Group configuration:
-Malleus Kill Team with two Terminators (both with TH/SS) and five Veterans (four with Missile Launchers/Flak Missiles and Bolters and one with DW Shotgun and Bolter), all on top of a Bastion with a Quad Gun.
The idea here is that the entire squad starts on the top of the Bastion, with the DW Shotgun Veteran manning the Quad Gun and the Terminators up front to tank enemy shooting with their 2+ armor and 3++ Invuls. Once the enemy Doom Scythe comes in, the Veteran manning the Quad Gun engages it (thanks to Interceptor and Skyfire) with 4 x S7 shots. Using re-rolls to Hit (because the Quad Gun is TLed) and to Penetrate (thanks to Malleus Doctrine), he averages 2-3 stripped HPs (or 1-2 HPs, if the Doom Scythe opts to Jink). If you are lucky, this kills the Doom Scythe outright, before it can even fire, but even it does survive, it probably Jinked, so it cannot shoot its Death Ray at all and its Tesla Destructor is MUCH less dangerous. When your shooting phase comes up next turn, the remaining four Veterans can shoot their 4 Flak Missiles at it using Malleus Mission Tactics and Malleus Doctrine, removing an average of 2-3 HPs (or 1-2, if the Doom Scythe jinks again), which either way should be sufficiently to destroy it. Like the PALADIN DRAKE Battle Group above, the IRON PIKE Battle Group is pretty specialized against Flyers and FMC in the Heavy Support slot, but can still use its shooting against various enemy flyers or skimmers and, if required, switch to Krak Missiles against enemy Heavy Support Vehicles/Infantry, thus maximizing Malleus Mission Tactics and Malleus Doctrine.
Overall, like before, these are not perfect Battle Groups but, just like Tau Crises suit builds, they each can do a specific “mission” quite well against some of the more crucial elements of a competitive Necron army and yet still are versatile enough to be included in a Deathwatch faction “all-comers” list, I think.