Editing Warhammer 40,000/7th Edition Tactics/Deathwatch (section)

===Battle Brothers===
*'''Space Marines:''' Throw these guys in to get more bodies with scouts and some other fun tools like grav-weapons and the FW stuff <strike>(Until such a time that FW allows you to hijack it for your own)</strike>
:*Who forgot that FW [https://www.facebook.com/ForgeWorldUK/photos/a.257098454307442.84604.257094630974491/1441653392518603/?type=3&theater already answered] this query? The Deathwatch have access to Thunderhawk Gunships, Caestus Assault Rams, Xiphon-Pattern Interceptors, Leviathan Dreadnoughts, Achilles-Pattern Land Raiders, and any Contemptor Dreadnought variant. 
**'''Iron Hands:''' A bare-bones Fist of Medusa provides a combination of durable long-ranged armored fire support, sorely lacking in your army with no access to foot Lascannons and AV13 tanks, and cheap-ish, hard as nails ObSec troops to take points and carry meltaguns. Their IWND, potentially ObSec Drop-pods with locator beacons and Deathwind launchers can be especially useful for your outnumbered and all-Deep Striking detachment. Also, they have access to both the cheesy Skyhammer Annihilation Force and the Librarius Conclave, though at this point you likely serve as their allies, not vice versa. And no Troop taxes for your IWND vehicles.
**'''White Scars:''' A Hunting Force and a Speartip Strike in a Scarblade potentially combine very well with your deep-striking footslog Veterans, they blow up enemy super-heavies, deathstars and tanks with grav and multi-meltas, and pin down or tie up their fire support, while you de-transport and clean up enemy troops with superior guns, missiles and special ammo. They can also Infiltrate scout bikes with locator beacons in convenient locations.
*'''Blood Angels:''' Amusingly enough, the Blood Angel Psychic Discipline's Primaris has a fair bit of potential to buff any of the Kill Team Cassius models, due to them all being characters. Jerek Suberei goes from amusing to bring a budget Eversor.
*'''Dark Angels:''' Ravenwing Knights in a Ravenwing Strike Force can bring an unholy amount of cheap-ish mobile plasma fire on Scout, Hit and Run, Skilled Rider, re-rolls Jink, potentially Stealth platforms, and are no slouches in melee either. Take their Attack Bikes to carry multi-meltas for you, and your Veterans will be free to bring their own infantry-destroying toys. Sadly, their Teleport Homers only work on your full Terminator squads, limiting their potential. The Ravenwing & Deathwing Terminators have a small selection of exclusive equipment that Deathwatch can't take.(Just like the Fluff!) Rift Cannons, Plasma Talons, Corvus hammers, Maces of Absolution plus Flail of the Unforgiven , Plasma Cannons and Plasma Storm Batteries are great for wrecking enemy MEQs. [[Troll|While a Deathwing Command Squad with an Apothecary and Land Raider DT will be very difficult to remove from an objective.]] TLDR: Dark Angels allies make spamming either Bikes, Terminators or both a viable strategy. 
*'''Grey Knights:''' Unless you care about Psychic terminators, then no need to apply. You have much better ranged firepower from Frag Cannons, and I dare say much better melee weapons (Xenophase blades and Great Thunderhammers beat out Daemonhammers for being S10 naturally and can Instant Death without Force). Skip. The Deathwatch are better against every army except Daemons (and that part is debatable, since Deathwatch has Xenophase weaponry).
*'''Space Wolves:''' Cavalry. Alternately, the Spear of Russ to add tank support if you choose.
*'''Imperial Guard:''' They have the bodies and excellent long range firepower. What else is there to say?
** A Cadian Battlegroup with the Emperor's Fist, Emperor's Blade, Emperor's Wrath formations and an Infantry Platoon can give you armored support, ObSec troops with special weapons, ample Blast and Skyfire artillery and multiple auto- or lascannon teams under orders respectively, leaving your Kill-Teams completely free to destroy enemy units. Also, their vehicles can take Augur Arrays for 25 pts to help you land Deep Strikes.
** For the lulz, put your Deathwatch kill teams on the back of a Stormlord and trollface your opponent as he has to come within megabolter range to use meltas. 
** The Guard gives Deathwatch something it sorely lacks, cheap expendable wounds and tarpits. A single Allied Detachment can bring over a hundred warm bodies onto the table for around 500 points with three attached ML 2 psykers at 75 points a pop. That is about cost of ten terminators with heavy weapons and a tin can to transport them in.
*'''Imperial Knights:''' Stick a Knight Crusader with a battle cannon and gatling cannon in the back for some much needed long range BRRRRRRRRRRRTTT to support your special space marine snowflakes. Anything gets close, stomp it out of existence. The knight should be enough of a distraction to let your marines pretend they are callsign Bravo Two Zero and get inside your opponents OODA loop and do their business.
*'''Militarum Tempestus:''' Your little brothers. Cheaper to MSU, as they cost 70 pts a squad to your 110 pts, easier to Deep Strike because of Move through Cover, can ObSec when taken in a CAD (and they don't have a Decurion so they don't lose anything this way), can bring 2 specials with 5 men, and have AP3 basic guns with good Orders. On the other hand, they are less durable and worthless in melee. They can have value, but you have to plan ahead how you are going to use them.
*'''Sisters of Battle:''' Honestly what the bolter babes can offer the Deathwatch is limited compared to other Battle Brother factions. Celestine makes a decent IC for your jump pack vanguard veterans, they make for cheap(er) suicide melta squads with multimelta transports and Exorcists are always fun for some long ranged shooting.
*'''Inquisition:''' Why haven't you taken it yet? Seriously, you get 3 Elites Choices (Read: 3 units of Inquisitorial Henchmen) and each of them can take a transport like a Rhino, or a Chimera or a Land Raider or a Valkyrie. That makes it worth it right up front, so this should be your first choice right here. Servo-skulls and Mystics will serve you very well for deep strike since every single unit in a Black Spear Strike Force has deep strike, but there is stunning overlap between Inquisition henchmen and how versatile your Veterans are.
**Take an inquisitor and 3 units of henchmen, each with a psyker and two acolytes. For under 80 points, you get a few units that can hold back field objectives while you let your Kill teams take the fight to the enemy and shoot things to shit, and 3 denial dice, which will help you hopefully stop a crucial power or two from going off when you don't want it too.
*'''Officio Assassinorum:''' A natural fit, both in fluff and in crunch, though there is some overlap. A Vindicare sniper is absolutely perfect for this army, allowing you to remove select MEQ-killing models from the table (such as plasmagunners), thus preserving the lives of your relatively squishy and expensive Veterans, and provides a modicum of heavy ranged anti-tank in the form of S10 AP2 Turbo-penetrators. He can also man a Skyfire emplacement, ignoring Jink when he does so. A Culexus is an excellent anti-psyker defence in case you didn't take Librarians, is a straight counter to psyker deathstar bullshit, and is a good [[DISTRACTION CARNIFEX]] in his own right. Callidus and Eversor are debatable, some of your Kill-teams are already tailored for the same purposes they serve (Dominatus, Purgatus and Furor), but they arguably do it better for cheaper and can augment your own efforts, and the Eversor is arguably the best DISTRACTION CARNIFEX in the whole game. A Black Spear Strike Force with an Officio Assassinorum Execution Force is a scary army to face indeed.
*'''Cult Mechanicus:''' All the Grav and Haywire you will ever require, some electro-priests with amazing dice output, and big MEQ-slaying robots. Generally not the best choice of ally for the Deathwatch, unless you also take a Knight and want to keep it in perfect condition, since they don't really do anything you can't.
*'''Skitarii:''' Can give you some good medium infantry to hold points or debuff enemies, decent outflankers, and excellent anti-air. A combination of Vanguard and Infiltrators can help your melee units to decimate powerful multi-wound enemies with near impunity, and you can give them transports, anti-horde and meltaguns, which they sorely need.
*'''Adeptus Astra Telepathica:''' Take an Astropath and upgrade it to ML2, then successfully cast a psychic power to reroll your reserves. Make like an Elysian and drop veterans from the sky while adding warpcharges to the pool.