Editing Warhammer 40,000/8th Edition Tactics/Deathwatch (section)

==Special Rules==
*'''And They Shall Know No Fear''': Re-roll failed morale tests, same as it is in the other Space Marine armies. 
*'''Defenders of Humanity''': Objective Secured, also like the other Space Marine armies. 
*'''Bolter Discipline''': We 2nd Edition now. All Adeptus Astartes and Heretic Astartes models using a Rapid Fire bolt weapon can take double the normal attacks (2 for bolters, 4 for storm bolters, etc) if at least one of the following is true:
**target is in half range
**if the model didn't move during the previous Movement Phase
**if the firing model is a Terminator, Biker, or Dreadnought
**This doesn't stack on top of itself, and you can't use this and Special Issue Ammunition at the same time, but the rule allows for Space Marine gunlines to be slightly more threatening. Standing still will give your Veterans the option of the full Rapid Fire benefit if you think SIA won't cut it, alongside Terminators and Bikers. Dreadnoughts have their full firepower at all times. Choose wisely between more Dakka or SIA.
*'''Shock Assault''': A brand new buff for all Space Marines, if a unit with this rule charges, gets charged, or performs a Heroic Intervention, models in the unit add 1 to their Attack characteristic until the end of the turn. This makes our boys in Black and Silver even deadlier, as the standard Vet. and Intercessor get 3 attacks on the charge. Never has there been a better time to run a 5 man squad of Heavy Thunder Hammers just for the chance to get 15 attacks against that vehicle you REALLY want dead.
*'''Combat Doctrine''': Feel like it's 7th edition all over again. Each of the three Combat Doctrines gives an AP-1 buff to different weapon types in your armies (non-cumulative with buffs from other sources). You have to use each Doctrine in order, starting with the '''Devastator Doctrine''', and once you switch there's no going back, so pay attention to the rhythm of the game. Your ''army'' gains this if ''all units in it'' have this rule, meaning taking a Guardsman Battalion or even a single Assassin CP'd in right before the battle would prevent the SM detachment from getting this rule, but allied SM detachments are ok even from a different chapter.
**On top of that, Chapter supplements give First Founding Chapters (and their descendants) a Specialist doctrine that is a bonus active on top of the regular doctrine. Bringing chapters with different specialist doctrines prevents either from getting theirs.
**These nifty rules will make your marines more efficient killers, but their rotation makes them predictable - devastate -> advance -> assault. Savvy opponents may try to break LoS to force movement penalties on your heavy weapons, rush for melee while you're still under the ranged doctrines, then fall back when you're finally under the assault one, scale buildings, etc. As such, don't be predictable yourself. Remember, you don't need to switch doctrines on the same turn they become available: surprise drop pod a target turn one or advance your infantry under cover of Devastation while your enemy remains confined to their hiding spots turn 3, what have you. The doctrines are as follows:
*#On Turn 1, your army will always start with the '''Devastator Doctrine''' turned on, giving all your Heavy and Grenade weapons the extra -1 AP so that you can soften entrenched infantry and cripple enemy vehicles from afar in preparation for your advance. Remember the first points of AP are the most important ones: AP-2 Heavy Bolters and Assault Cannons are more noticeable than AP-4 Lascannons. Do keep in mind the plethora of sniper rifles and Heavy Flamers (Incendium/Inferno/Flamestorm cannons) are Heavy Weapons too. The boost to Grenades matters only to Intercessors for the most part.
*#On the 2nd turn you switch to '''Tactical Doctrine''', shifting the boost to your Rapid Fire and Assault weapons. Be it to close the distance to the enemy or because your vehicles are about to give their last, this mostly passes the ranged baton to your infantry. And a bolt rifle going from AP-1 to AP-2 is more noticeable than a lascannon going from AP-3 to AP-4. Storm bolters and auto bolt rifles work wonders here. 
*#On the 3rd or 4th turn you shift to '''Assault Doctrine''' (you MUST change to assault on the 4th turn) giving the extra AP to your Pistol and Melee attacks. Don't. Forget. Your. Pistol. The first point of AP is the most important one - chainsword/CCWs benefit the most, while AP-4 on a sword can become excessive.
**As of the 02/27/20 FAQ, you MUST change from Devastator to Tactical on turn 2, and then change to Assault on turn 3 or 4. This will force you to keep at least a few units that are capable of fighting in CQC, as you can no longer just bum around in Devastator or Tactical doctrine and persist on blasting things from across the map.
**Combat Doctrines are specifically stated to work with Special Issue Ammunition, however, AP limits for Vengeance and Kraken rounds are still still in effect.
===Mission Tactics===
At the beginning of each battle, all units with this rule (e.g. infantry, bikers, and Dreads) gain the ability to re-roll 1s to wound against anything belonging to one chosen battlefield role (i.e. against all enemy HQs, or all enemy Troops, or all enemy Heavy Support, etc). Several methods exist for switching the Mission Tactic mid-battle, allowing for considerable versatility.

The Tactics and their corresponding target battlefield roles (re-roll 1s to wound against all enemies from that role) are as follows:

*'''Furor Tactics''': Troops
*'''Venator Tactics''': Fast Attack
*'''Dominatus Tactics''': Elites
*'''Malleus Tactics''': Heavy Support and Lords of War
*'''Purgatus Tactics''': HQ
*'''Raptoris Tactics''': Flyers

===Special Issue Ammunition===
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Any weapon from the following list may may choose to fire special issue ammunition. All models in a unit must use the same SIA, even if targeting separate enemy units, unless using the Optimized Volley Stratagem.
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*Absolvor Bolt Pistol
*Auto Bolt Rifle and Master-crafted Auto Bolt Rifle
*Bolt Carbine
*Bolt Pistol
*Bolt Rifle
*Boltgun and Master-crafted Boltgun
*Combi-Flamer, Combi-grav, combi-melta, and combi-plasma (boltgun profile only)
*Guardian Spear
*Heavy Bolt Pistol
*Hellfire Extremis (boltgun profile only)
*Stalker Pattern Boltgun
*Stalker Bolt Rifle and Master-Crafted Stalker Bolt Rifle
*Storm bolter
*Twin Boltgun
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Rule of thumb is choose the ammo that affects whatever the enemy has in abundance. [[Eldar|Multiple debuffs to hit?]] Dragonfire. T5? Hellfire. None of the above/Wears cardboard or better? Kraken. Vengeance, if you are in range. Note you cannot use Bolter Discipline while using any of these ammo choices. 
*'''Dragonfire Bolts:''' Add +1 to hit when shooting at a unit in cover. This is okay, but Space Marines are pretty decent shots already. The real problem with units in cover is not that you can't hit them, but the fact they get better saves, and Kraken helps with that. Where it does shine is against light units that hog cover and have To Hit debuffs; Eldar Guardians & Rangers are the most blatant example, but Jormungandr Tyranids, Stygies AdMech, and the like fit the bill too. Anything with either T4 or a 4+ save is better dealt with other things.
*'''Hellfire Rounds:''' Wounds [[Awesome|everything except vehicles and Titanic units on a 2+]], which '''against T5 and up is far better than other ammo types'''. Improving wounding from 5+ to 2+ means 2.5x the damage output of ordinary bolts, and improving from 6+ to 2+ means increasing damage output by a whopping ''5x'' that of ordinary bolts. To compare with the penetration bonus from Kraken, AP-1 is only 2x damage against 2+ saves, and 1.5x damage against 3+ saves. Considering the new 8E wounding chart and how difficult it is to get a 2+ To Wound these days, Hellfire rounds are golden.
**The addition of Mission Tactics can turn this into a re-rollable 2+ to wound when targeting units with the right Battlefield Role, so exploit this if your opponent fields a lot of units that have a common Battlefield Role. Basically this is a 97.2% chance to wound, greatly simplifying mental estimates (and turning your enemies into mulch).
*'''Kraken Bolts:''' Add 3" to the range if the affected weapon is a pistol, 6" range otherwise. Improve the AP by one to a maximum of -2. This essentially turns your Boltgun into a Bolt Rifle, and your Bolt Rifle into a better Stalker Bolt Rifle. Mighty useful, since it both debuffs AND lets you play with range: turns your Bolter into a Bolt Rifle, an Autobolt into two Bolt Rifles, a Bolt Rifle into a better Stalker Bolt Rifle, SBRs outrange Heavy Bolters, etc. But most importantly, ''it might put the enemy in Rapid Fire range'': while one Hellfire round can be a bigger improvement, '''''shooting two Kraken rounds is simply better'''''.
*'''Vengeance Round:''' Subtract 3" from the range of your pistol or 6" from other weapons. Improve the AP of the weapon by two to a maximum of -3.  Phenomenal ''when you're in range for it'', given that Bolters normally have AP0; against 2+, this is 3x output, and 2x against 3+. '''The best ammo against T4 and smaller''', unless Kraken gets to shoot twice.
**Bolt Rifles, Stalker Bolters & Stalker Bolt Rifles become like budget Plasma Guns/Incinerators, able to deliver AP-3 at comfortable range, from a unit in the Troops section.
**Mind the range reduction! Since deepstrikers arrive at ''MORE'' than 9" away, this means Termie Stormbolters ''won't'' be in RF range, and Reiver Heavy Pistols won't get to shoot at all. Bolt Carbines and Auto Bolt Rifles, being Assault 2 instead of Rapid Fire, don't have that much of a problem.
**DO NOT USE AGAINST VEHICLES ''ON ITS OWN''. Not even against anything Gravis-sized, really. Vengeance rounds, though AP-3, still only do 0.15 wounds against those targets since the Strength value of the attack is unchanged. Want to kill a Sentinel using Vengeance? Get ready to shoot it 40+ times, then. Really, ''that's what the Tempest Shells Stratagem is for.''

===Mixed Units===
If you have a squad with mixed toughness scores (by adding bikes to a veteran squad for instance), you use the majority toughness for the unit. If there is an even split, you choose.