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I've been looking back on Necron infantry in general as one of my buddy's runs Necrons and we got quite a few games in together. One of the things that stood out to me was how little variety exists in their range for normal Necron soldiers.

Yes Warriors basically have 2 separate flavors of Gauss, short ranged high punch, and longer range but a weaker weapon.
Yes Immortals have their Gauss Blasters, which kinda combine the strong points of both of the Warrior's guns or they can take a Tesla carbine for infantry frying.

Outside of them you have your 2 melee options for Lychguard and 2 options for Praetorians. I also wouldn't mind multipart kits for some of the Necron Characters, throw in some variation in the equipment. I doubt all Royal Wardens carry the same Relic Gauss Blaster, much as I think Necron Lord and Overlords are some of the most uniquely equipped leaders in the galaxy save for perhaps Ork Warbosses and Big Meks.

What I personally think would be a nice touch is too introduce more variation in armament into the ranks of the Necron Legions, without having them succumb to the Flayer Curse, or go insane and become Destroyers.

Drawing from that basis I figure Immortals entrusted with more esoteric weaponry than the normal ones, give them some sort of unique name compared to the rank and file Immortals. Immortal Purifiers or Immortal Exterminators.

Necrons with Flame Throwers is a niche I personally think is rather unexplored. My idea is that you'd have a small unit carrying essentially realistic plasma guns (which would be closer to flame throwers than anything else) and carrying the strength and power of a plasma gun, but using Flamer rules, perhaps a Strength 6-8 AP-3 D1 or 2 weapon. These soldiers could also carry those Dispersion shield the Lychguard use, holding their Plasma weapons in the other hand.

Price these guys at 25-35 ppm, with a buffed up Immortal statline, with a weakness against melee units (provided those melee units survive their firepower).

My Second idea for an option for these same troops draws more on the influence of War of the Worlds. Necron Immortals carrying a Chemical weapon analog spraying forth streams of black poisonous vapors that choke the life from living beings while leaving Necrons untouched. Perhaps with a unique rule allowing them to be fired into melee combats with their own units since they pose little risk of actually harming any of their own soldiers or leaders. Give these guys another option allowing them to carry Heat Rays or some sort of small Death Ray and it would further draw upon this theme.


I like the picture of the walls of Green beams ripping targets to pieces but I imagine that fighting the Necrons would include far more variation in how they'd bring death, they did fight a massive Galaxy spanning War against the Old Ones, who knows what weaponry they wrought to face down their enemy.

This is mostly idea hammer but I'm curious as too what you guys think.

I can dig it. A couple of thoughts:

panzerfront14 wrote:


Necrons with Flame Throwers is a niche I personally think is rather unexplored. My idea is that you'd have a small unit carrying essentially realistic plasma guns (which would be closer to flame throwers than anything else) and carrying the strength and power of a plasma gun, but using Flamer rules, perhaps a Strength 6-8 AP-3 D1 or 2 weapon. These soldiers could also carry those Dispersion shield the Lychguard use, holding their Plasma weapons in the other hand.

Price these guys at 25-35 ppm, with a buffed up Immortal statline, with a weakness against melee units (provided those melee units survive their firepower).

Iirc, the necron "flamer" (the hand of flame) is basically a device worked into a hand so the noble wielding it can literally shoot fire from his hand. Aesthetically, I wonder if other template weapons would be built into the hand.

I'd lean towards making them S7, AP-3, D1, Assault d3, Blast. Basically, give them a "safe plasma" profile with no option to overcharge because 'crons don't seem like they should be randomly destroying themselves. I feel weird about limiting it to d3 shots, but auto-hitting with high strength, good AP attacks seems pretty powerful. The closest infantry-mounted weapon I can think of are eldar d-scythes. Not sure if the dispersion shields the lychguard wield are considered "special" enough to make handing them out taboo.

My Second idea for an option for these same troops draws more on the influence of War of the Worlds. Necron Immortals carrying a Chemical weapon analog spraying forth streams of black poisonous vapors that choke the life from living beings while leaving Necrons untouched. Perhaps with a unique rule allowing them to be fired into melee combats with their own units since they pose little risk of actually harming any of their own soldiers or leaders.

Makes a lot of sense, and having the weapon not affect all microbial life would give you an excuse to not give such weapons to destroyers. My only fluff concern is that chemical poison seems a little low-tech for 'crons? Like, I feel like 'crons would be reluctant to use anything that would require resupplying physical ammo. I kind of like the idea of the black vapors actually being nanites that shoot out, attack anything organic, then get recalled back into the weapon for later use. Fits the waste-not-want-not feel of the 'crons. But then, nanites could potentially go after metal too, so maybe that defeats the point.

I like the picture of the walls of Green beams ripping targets to pieces but I imagine that fighting the Necrons would include far more variation in how they'd bring death, they did fight a massive Galaxy spanning War against the Old Ones, who knows what weaponry they wrought to face down their enemy.

That's a solid point. The prevalence of gauss/tesla makes me think that 'crons generally valued the logistical advantages of just having everything run on energy generators, but they did presumably spend a lot of time fighting a variety of organic enemies. There's aesthetic value in keeping warriors very same-y in their loadouts, but immortals presumably have enough free will to be trusted with more powerful and complicated weapons.

So Wyldhunt I choose some of those effects because I felt they fit into a sort of theme that GW is establishing for Necrons, some of their new constructs really nail the War of the Worlds vibe that I frankly love so I based these sorts of effects and descriptions upon them.

What I'm picturing for the Immortals with Flame weapons is a guy with a shield, a necron looking flame weapon and a cloak similar to that one immortal leader or the Royal Warden, demonstrating a higher level of status over the other immortals but he still isn't a Noble. Call them Immortal Purifiers and perhaps have them lean into durable elites of the Immortal caste. A sort of Elite force employed to flush out stubborn holdouts in support of greater Necron aims.

The other set, Immortal Exterminators, specially configured for war against some of them more physically resilient foes of the Necrons. I picked the Black Gas as it really stuck out to me when I read War of the Worlds, since at a young age it was the first time I heard of chemical weapons. Taking that Inspiration I imagine Necrons could easily find a way to compress Gasses far beyond what we or the IOM can manage and release them in torrents. Another potential weapon for these soldiers could be Heat Rays, just as a potential source of additional AT. But the driving theme I'd like to work with is that they are focused on removing hardy targets that might impede the rest of the Immortal Phalanx.

In terms of rules I figure a Immortal statline is a good starting point perhaps with some sort of additional shielding or Necron super science.

"The Black Gas Projectors" in my mind are either blast weapons or flamer type weapons, though I'm inclined to go more towards long ranged flamers. 18 inches d6 autohits, Strength 1, AP-2 D2

However I would essentially give it Poison 3+, ignores cover, and a special rule where it can be fired into combat though with caveat that it can't fire into combat if your opponent is also Necrons needing to switch to ammunition which can damage Necrodermis.

Once upon a time the lack of variety of infantry was one of the thematic features of the faction...

 Lord Damocles wrote:
Once upon a time the lack of variety of infantry was one of the thematic features of the faction...

Doesn't mean it's good to keep that.

I think Plasma Flamers are cool, but you'd have to be careful with their power level, of course. Should probably belong in Heavy Support, maybe Elites.
Same for the gas guys.

While I'd like to see harder numbers on these ideas, the concepts are cool!

 Lord Damocles wrote:
Once upon a time the lack of variety of infantry was one of the thematic features of the faction...

The "horde of nameless, skeletons" angle is still pretty well covered by warriors. If you want to lean into that, the option is still there.

@panzerfront14
I like the bit about being able to fire into melee if you're *not* facing fellow necrons. 'Crons absolutely can cram a ton of stuff into a limited area. Heck, they can create pocket dimensions if they need to. I'm just not sure if they'd be up for taking the time to refill that pocket dimension every now and again. But I won't dwell on it.

I'm not sure if "removing hardy targets" would be a goal 'crons would use gas for. "Hardy" makes me think there's a good chance the target is wearing armor (or is a vehicle) which makes me think there's a good chance the target has a sealed-off air supply, advanced respirator, etc. Like, a terminator is probably really good at not breathing in poison if his helmet is on. Plus, their basic weapon is gauss which is supposed to be good at steadily wearing away physical material while RP makes the guys using the gauss durable enough to outlast the target. I can absolutely see 'crons using gas, but it seems to me that they would use it to efficiently clear out a bunch of organic enemies that have dug into cover; sparing the 'crons the effort of lining up a gauss shot with every enemy individually.

That said, your suggested stats for the gas guns seem fine to me. I think you can reasonably justify each part of that statline. Then again, I also feel like most parts of that statline could also reasonably be toned down. Most "flamer" type weapons have 12", so 18" feels like a bit of a one-up. (Although tau falmers are 18" iirc, so meh.) Wounding on a 3+ probably isn't broken, but it does give my Poison(4+) drukhari poison envy. AP-2 sort of makes sense in that a lot of light armor doesn't really protect against gas, but then again tau and eldar armor seems like it maybe should. Power armor seems like it should keep the wearer perfectly safe from gas, but then I guess we can assume that there are little openings in the armor created by previous attacks. D2 is pretty reasonable given that the exact level of lethality of the poison can be whatever you want. But then again, letting marines and nobz be a bit harder to gas to death than guardsmen would be fluffy.

Basically, I don't really have a problem with your proposed statline, but I think it might be equally or more fluffy to make them 12", S1 (Poison 4+), AP-, D1, Pistol d6. (With the gimmick being that you can shoot them into combat.) Note that making them blast would prevent the wielders from shooting them while in combat, but maybe that's a feature rather than a bug.

 JNAProductions wrote:

 Lord Damocles wrote:
Once upon a time the lack of variety of infantry was one of the thematic features of the faction...

Doesn't mean it's good to keep that.

I think Plasma Flamers are cool, but you'd have to be careful with their power level, of course. Should probably belong in Heavy Support, maybe Elites.
Same for the gas guys.

While I'd like to see harder numbers on these ideas, the concepts are cool!

Alright I'll attach some hard numbers to them

Fluff: Elite Immortals selected to bear Purifier Rays, these soldiers cleanse the strongest of the foe's soldiers from the field in gouts of white hot Plasma. These Warriors hail from the War against the Krork where their armament would ensure no linger trace of their ancient foes remained to continue the battle against their forces. They were heavily reinforced by Crypteks to withstand the trials of battle and now serve as fell protectors of a Dynast's claims, or as shock troops against his foes. Many were called back into service following the opening of the Great Rift and ordered to send the shrieking horrors of the Warp back to their proper place.

Immortal Purifiers, Battlefield Role (Elite or Heavy Support)

35ppm M5 WS 3+ BS 3+ Str 5 T5 W2 LD 10 (am undecided if they should be 3+ or 2+ native, am leaning towards 3+ since thats what Lychguard have)
Weapons:
Purifier Rays: Range: 12 inches, type Assault D6, Strength 7, AP-3 Damage: 1. Abilities: Each time an attack is made with this weapon, that attack automatically hits the target.
Wargear:
Dispersion shield: The bearer has a 4+ invulnerable save. In addition, add 1 to armour saving throws made for the bearer.
ABILITIES
Reanimation Protocols, Command Protocols


Fluff: Emerging from dark clouds, Necron Exterminators are specially equipped Immortals bearing weapons from their long ago war against the Old Ones. Devised with help from the C'tan Shard Aza' Gorod these weapons fire projectiles into the ranks of the living which burst to release a roiling gas antithetical to all life. It is able to slip through all but the finest and densest of filters, leaving nothing but lifeless corpses in its wake. These weapons are considered dishonorable by some nobles, but no Dynast will deny that their effects are among the most efficacious against the living. In desperation, the Cryptek's of the a dishonored Dynasty even created a variation which deployed swarms of Nanosacrabs, able to strip enemy Necrons into their consitution pieces. This practice saw that Dynasty destroyed on order from the Triarch Praetorians but some samples of these dread weapons escaped and have since blighted several dynastic conflicts, their usage being a sign of supreme disrespect towards their opponents. Some Dynasties have begun fielding entire Phalanxes of their warriors, who when massed will darken the battlefields of the 42nd Millienium with ancient terror.


Immortal Exterminators, Battlefield Role (Elite)
22ppm M5 WS 3+ BS 3+ Str 4 T5 W1 LD 10 Sv 3+
Weapons:
Black Gas Projectors : Range: 30 inches, type Assault D6, Strength 1, AP-2 D2. Abilities: Blast, Ignores Cover, Automatically wounds non vehicle units on a 3+.
Wargear:


ABILITIES
Reanimation Protocols, Command Protocols
I'm trying to think of a rule to buff their durability, either through an additional save, or some sort of defensive debuff against enemy shooting.

Bespoke Rules:
Flesh Seeking munitions: Black Gas Projectors may be fired into combats containing friendly units, unless your opponent's units have the Keyword (NECRONS)

@Wyldhunt, when I meant Hardy Target, I was envision heavily dug in forces, not Terminators or even Marines for that matter. A bias I've picked up through my military service I guess. Though I can imagine that it is a bit confusing.

panzerfront14 wrote:
Immortal Purifiers, Battlefield Role (Elite or Heavy Support)

30ppm M5 WS 3+ BS 3+ Str 5 T5 W2 LD 10 (am undecided if they should be 3+ or 2+ native, am leaning towards 3+ since thats what Lychguard have)
Weapons:
Purifier Rays: Range: 12 inches, type Assault D6, Strength 7, AP-3 Damage: 2. Abilities: Each time an attack is made with this weapon, that attack automatically hits the target.
Wargear:
Dispersion shield: The bearer has a 4+ invulnerable save. In addition, add 1 to armour saving throws made for the bearer.
ABILITIES
Reanimation Protocols, Command Protocols

Fluff good.
But compare them to Flamers.

T5 2+/4++ W2 Reanimation is reasonably comparable to T4 6+ Melee/3+ Ranged Daemon W3
But Flamers get 6.5 shots at BS 3+, for 4.33 hits. That's a little better than 3.5 autohits, though it is vulnerable to hit penalties. However, they are S5 AP-2 D1 hits. Your hits are S7 AP-3 D2.
The only major downside they have is a much shorter move. If you're happy with the statline, I'd recommend a hefty points increase.

panzerfront14 wrote:
Immortal Exterminators, Battlefield Role (Elite)
20ppm M5 WS 3+ BS 3+ Str 5 T5 W1 LD 10 Sv 3+
Weapons:
Black Gas Projectors : Range: 30 inches, type Assault D6, Strength 1, AP-2 D2. Abilities: Blast, Ignores Cover, Automatically wounds non vehicle units on a 2+.
Wargear:


ABILITIES
Reanimation Protocols, Command Protocols
I'm trying to think of a rule to buff their durability, either through an additional save, or some sort of defensive debuff against enemy shooting.

Bespoke Rules:
Flesh Seeking munitions: Black Gas Projectors may be fired into combats containing friendly units, unless your opponent's units have the Keyword (NECRONS)

Fluff also good.

However, for 4 PPM over an Immortal with a Gauss Blaster, you get...

+1 Strength on the statline
+2.5 shots at 15-30 inches, +1.5 shots at 15 or less inches, assuming no Blast bonus
+1 to-wound T3 and T4 models, +2 to-wound T5 models (excepting Vehicles), and +3 to-wound anything T6 or above that's not a Vehicle
+1 Damage
The ability to fire into friendly combats.

You do lose ObSec because they aren't Troops, but you can gain that back with a Dynasty, so... Yeah.

I would like there to be a canoptek troop unit.
Either move scarabs to troop or have some sort of mobile sentry sort of thing.

Whilst it is try that Necrons having little variety and not being super customizable is a theme of theirs to reflect their mechanical and uniform nature, having specialists who have a singular purpose is also something of a theme.
Gas weapons don't really seem like a necron thing to me though. They seem to prefer to use lightning, nanites or psychological warfare as crowd control / trench clearing options. They do have flame based weapons, but those are pretty rare for some reason; only the triarch and nobility seem to use them.

Maybe something like a Grey Goo dispenser that just vomits out carnivorous nano-scarabs would be more thematic for them.

JNA you raise a good point, I adjusted the points themselves when I was working with an early variation of this in my head. Perhaps 35ppm, I also intended them to come in units of 3-6, to limit them from becoming oppressive, perhaps shoving them in a high competition slot as well, either Elite or HS.

The Gas Crons could also afford a jump to 25 points per model plus a small max squad size.

Even a unit of 5 is incredibly undercosted. Those flamer just pump out too much damage. Against a T7 3+ unit it puts out 15 wounds. Against T4 3+ it does 19 wounds. T8 2+ is 8 wounds. They’re on an incredibly durable platform with a 2+/4++ T5 unit with reanimation and 2W. All of this assumes average rolls and no buffs. Even at 35 ppm this unit is a steal.

I’d suggest toning things down if you don’t want to up the cost. Making the weapon D1 when auto hitting and maybe D2 for an assault 1 shot that still has to hit. Dropping the invul to a 5+ also would be a good bet.

Firing into close combat is also a huge feels bad mechanic. Any unit that is going to disregard core rules should be incredibly expensive. I get the lore argument behind it but there’s plenty of armies with justification for shooting into combat as well. It’s a mechanic in the game though that shouldn’t really be messed with in my opinion.

Would it be reasonable to make the plasma flamers Assault d3 instead of Assault d6?

I know that d3 has less of a "fwoosh!" feeling to it, but halving those numbers evil_kiwi_60 just listed is probably a lot more reasonable. You'd still be wiping out about 5 marines with a volley. You'd still be almost one-shotting a rhino on average. You'd still be auto-hitting, ignoring cover, and upping your damage output against hordes (via blast),

You could also consider lowering the strength to 6 (in addition to or instead of lowering the number of shots to d3). This would be inkeeping with some of the "safe" plasma weapons in the game (like hellblasters' assault 3 gun) and would put a dent in the damage output against T6 and T7 targets. (Still arguably overperform against T8 2+ though.)

Alternative alternative: maybe just lower their Damage to 1. Halves your overall damage output like lowering your shots. Lets multi-wound models actually use their second wound (feelsgood). Still lets you reliably hurt a rhino, but you're more likely to lower its damage bracket than to one-shot it. Retains your current effectiveness against dug-in W1 targets (which seems to be the main use case you have in mind for this weapon.)

Yeah, going to D1 also works. Perhaps a solid 35-40ppm cost is also a decent idea. Though I lean more towards 35 if they're D1. Its also in line with my Plasma Flamethrower idea. Plasma largely only goes to D2 when its Strength 8 so Str 7 Plasma Flamers make sense at D1.

That would bring them down from 19 wounds vs a MEQ statline to 8.5 which is still most of a base Intercessor squad, but you're paying 175 points to burn down 90 pts. If that still feels too good we could then switch to D3 profile. 200 points is big chunk of a 2k army, about 10% or so but I can see them costing that much too.

I'd like to keep them as tough since I figure thats a Necron sticking point but being flexible with the points is something I'm game for.

The 2+ to wound non vehicles on the Gas Immortals is a typo, should be 3+.

You could do it like GW and turn the ability to shoot into combat and/or the D2 into stratagems costing 2CP.

I only have maybe a dozen games played under my belt, all casual games with friends, but we have always allowed certain factions to shoot into combat according to their fluff. We experimented with just 1's or all misses hit the friendly and it seems like a big enough tradeoff to me.
I once had my Broadside try to snipe a Stompa in a melee with my friend's titan, and I rolled a 1, hitting my friend, then rolled a 6 to wound, making it bonus railgun damage. Oops!

I think a flamer-type weapon would fit the Necron well because how do they deal with small swarming enemies with only their single-shot gauss beams? Makes no sense.

 kingpbjames wrote:
I think a flamer-type weapon would fit the Necron well because how do they deal with small swarming enemies with only their single-shot gauss beams?

Well, they'd probably use their own small swarming things (scarabs) or tesla (arcing lightning to hit multiple nearby targets after firing into the swarm). Not that I'm trying to talk anyone out of 'cron flamers.

Ah, shows how much I know. Haven't gotten to play against Necrons yet but I hope to build an army for myself some day...

So to set them apart from tesla carbines I do like the idea of some unworldly and nasty green flames, maybe more along the lines of a compressed gas blowtorch with shorter reach than liquid jetting flamethrowers.

 kingpbjames wrote:

I think a flamer-type weapon would fit the Necron well because how do they deal with small swarming enemies with only their single-shot gauss beams? Makes no sense.

I mean, they used to have access to tiny scarabs that burrow their way into people's brains and mind controlled them, so they probably could make a swarm of scarabs that just eat you.
I miss Mind Shackle Scarabs. That was some great cheese. Then people got salty because they couldn't roflstomp necrons anymore with their beatsticks.

Going down to damage 1 or assault d3 with S6 would definitely help balance the unit out. The unit would remain a significant threat to almost any infantry while no longer picking up all but the heaviest tanks. I think the damage 1 option is the better of the two because it has been a vicious cycle of creep for D2 weapons to make up for 2 wound armies to make up.... you get the idea.

I would look at the durability too though. The unit has a T5, 2 wounds, 2+/4++ with reanimation protocols. This is roughly the statline of a space marine terminator which is T4, 3 wounds, 2+/5++ for 33 points. A chaos terminator with the same stat line comes in at 36. A blight lord terminator at T5, 3 wounds, 2+/4++, and disgustingly resilient tops out at 40. Of these the closest stat line is probably the blight lord. At that resiliency and with good damage this unit should probably come in closer to 40ppm.

Realistically what armies can't justify shooting into close combat? Some marine chapters, the eldar, custodes, and maybe the Tau?

 evil_kiwi_60 wrote:

I would look at the durability too though. The unit has a T5, 2 wounds, 2+/4++ with reanimation protocols. This is roughly the statline of a space marine terminator which is T4, 3 wounds, 2+/5++ for 33 points. A chaos terminator with the same stat line comes in at 36. A blight lord terminator at T5, 3 wounds, 2+/4++, and disgustingly resilient tops out at 40. Of these the closest stat line is probably the blight lord. At that resiliency and with good damage this unit should probably come in closer to 40ppm.

Pretty sure they're basically just lychguard with a weapon swap, no?

Realistically what armies can't justify shooting into close combat? Some marine chapters, the eldar, custodes, and maybe the Tau?

I'm of a mixed mind on this. While a lot of armies wouldn't mind blasting away their comrades along with the enemy, a lot of factions as a whole might not exist if you make that tactic a regular part of your playbook. Like, drukhari will straight up enjoy shooting their allies by "mistake," but also good luck convincing a wych cult to join you on a raid if your kabalites are known for pulling stunts like that. And if you're powerful enough to make them join you on the raid anyway, you've given one of your murderous minions a really strong motivation to assist in your destruction as a matter of survival. (On top of all the other reasons they already wanted to kill you.) I think the same idea generally holds true for most of the factions in the game. Marines can't replenish their losses fast enough to regularly bolter each other to death. Kroot would probably be way less willing to serve as meatshields if fire warriors start shooting them in the back. Guard morale is going to be tested if being infantry means being a mortar magnet. Even orks might be inclined to krump all their flashgitz if the rich gitz keep shootin' up all yer ladz while they're tryin' to have a good throwdown with some humies.

EDIT: Even chaos marines have to be careful about putting the pie plate over each others' heads. This is kind of a plot point in Harrow Master. Though they're probably generally fine with blasting away some cultists.

I don't have a good excuse for tyranids though. They obviously don't want to risk biomass/waste energy (creating bodies takes calories) more than they have to, but if the hivemind determines that blasting some terminators while they're bogged down in gaunts is the best play, there shouldn't really be any concerns of morale or honor or whatever preventing the biovores from opening fire. I guess maybe the instincts that prevent the bugs from killing/eating one another are strong enough to require more conscious focus to override than the hive mind is normally willing to commit? Like, you can punch yourself in the face hard enough to seriously hurt yourself if you really try, but your instincts are going to make it kind of difficult.

 Wyldhunt wrote:

Pretty sure they're basically just lychguard with a weapon swap, no?

I'm of a mixed mind on this. While a lot of armies wouldn't mind blasting away their comrades along with the enemy, a lot of factions as a whole might not exist if you make that tactic a regular part of your playbook. Like, drukhari will straight up enjoy shooting their allies by "mistake," but also good luck convincing a wych cult to join you on a raid if your kabalites are known for pulling stunts like that. And if you're powerful enough to make them join you on the raid anyway, you've given one of your murderous minions a really strong motivation to assist in your destruction as a matter of survival. (On top of all the other reasons they already wanted to kill you.) I think the same idea generally holds true for most of the factions in the game. Marines can't replenish their losses fast enough to regularly bolter each other to death. Kroot would probably be way less willing to serve as meatshields if fire warriors start shooting them in the back. Guard morale is going to be tested if being infantry means being a mortar magnet. Even orks might be inclined to krump all their flashgitz if the rich gitz keep shootin' up all yer ladz while they're tryin' to have a good throwdown with some humies.

EDIT: Even chaos marines have to be careful about putting the pie plate over each others' heads. This is kind of a plot point in Harrow Master. Though they're probably generally fine with blasting away some cultists.

I don't have a good excuse for tyranids though. They obviously don't want to risk biomass/waste energy (creating bodies takes calories) more than they have to, but if the hivemind determines that blasting some terminators while they're bogged down in gaunts is the best play, there shouldn't really be any concerns of morale or honor or whatever preventing the biovores from opening fire. I guess maybe the instincts that prevent the bugs from killing/eating one another are strong enough to require more conscious focus to override than the hive mind is normally willing to commit? Like, you can punch yourself in the face hard enough to seriously hurt yourself if you really try, but your instincts are going to make it kind of difficult.

Lychguard are a very efficiently costed unit but certainly an autohitting AP-2 weapon should be more than 5ppm.

The problem is it is all relative. If you're a guardsman about to get overrun by any of the horrible armies, that mortar shell is probably a mercy killing. We see marine chapters like the Marines Malevolent use this as a deliberate plan. Khorne doesn't care from where the blood flows and Iron Warrios use cultists to clear minefields with their feet. Tau for similar reasons to the guard or sacrifice for the greater good. We can talk in circles around this but in general there are so many sub factions that you can't really make a concrete statement on who would and would not target their own units. Even with modern armies, heavy weapons will be used in close proximity to friendly forces in dire situations.

I don't want to keep derailing the topic, but in my mind, orks and tyranids are the only two factions that wouldn't hesitate to shoot through their own. The other factions might make that call under certain circumstances but orks would do it for fun and the tyranid hivemind is a cold and calculating insect lord.
If anything, I'd think the necrons would be least likely to risk sacrificing their own endangered species. That would make a gas-type weapon that they are immune to all the more interesting.

Points can be pretty flexible on these Necron boys, biggest reason why I proposed this is because I doubt that they've explored the various Xenos Factions as much as they've done the IOM. I figure starting by adding on some variety to what the Necrons considered their line soldiers would be a good idea. I imagine Immortals would be one of the most diverse castes besides Crypteks among the Necrons.

Crunch wise, sure 40ppm would still be pretty good for these guys considering they're tough, have strong weapons and can get buffs from outside sources as well.