Hiyas!

This is a pretty old idea, but I've only now gotten around to really flesh it out. Basically, this weapon is intended to be the professional's flame bomb, and something which I deem still missing from the official rulebooks. I'd appreciate some feedback on whether you think it is too powerful or perhaps not dangerous enough. Given that it employs a lot of modificators, it is entirely possible that I've missed the mark. It also includes a new weapon quality, Corrosive , which could be used for acid-based weapons as well. I've read a lot of posts about the flame-based weapons here, so I know it can be a tricky subject.

Phosphor Grenade

Phosphor grenades are the military variant of the rather crude and improvised flame bomb. Filled with highly incendiary white phosphorus that self-ignites on contact with air, they procure both a hail of sticky, glowing gobs as well as a screen of hot white smoke, making this weapon capable of causing serious burns and a painful death. This kind of grenade is quite popular with elite Imperial forces such as Stormtroopers or, in particular, Adepta Sororitas Battle Sisters, in case of the latter no doubt owing to the Ecclesiarchy's penchant for the purifying effect of flame. Larger versions can often be found amongst the loadout of Imperial Navy Marauder bombers. They are most effective when employed against groups of Orks and Tyranids or similar xeno-creatures, but work equally well in the confined spaces of a city whose inhabitants have turned away from the Emperor's light.

Characters hit by this weapon will suffer 1d10 wounds per round as the phosphor eats through their body. After 1d5 rounds, the small globs will be either burnt up or choked by the unfortunate victim's blackened flesh.

As per the Game Master's decision, the area affected by the blast may catch fire. Characters not hit by the phosphorus but moving through the area are subject to the normal rules for catching fire as detailed on DH page 210.

Range: SBx3
Damage: 1d10+5E (as with all flame-based weapons, the target may roll Agility to evade)
Penetration: 2
Weight: 0.5kg
Cost: 60
Availability: Rare

Special Traits

• Blast (3)
• Smoke (Duration 1d5 rounds, limited to 2x Blast Area)
• Proven (minimum of 3 on damage die)
• Flame (target taking damage must succeed on Agility -20 Test or is set ablaze and suffers 1d10E/round with no reduction for armour; duration 1d5 rounds)
• Corrosive (target's Toughness Bonus is halved for the purpose of calculating wounds; Agility Test to stop the burn has an additional -10 penalty)

White Phosphorous is exremely dangerous and powerful. My Commander and his whole crew were burned alive by a white phosphorous device in March 10, 2008. Most of the Hum-Vee was as well destroyed. One thing to remember is that putting out white phosphorous is extremly difficult. You either have to TOTALLY imerse it in water(highly unlikly unless a large body of water near.) Or smother it with mud/sand or specifficly designed chemicals. The damage you proposed might even be on the low side, but it is deffinatly not on the high.

Ouch... I'm sorry to hear that. WP truly is a terrible weapon and no human being deserves to be subjected to it. That said, I suppose this is true for most things you find in 40k. As you may have already guesses, I got the initial idea for this one from DoW:Soulstorm. It's a fitting weapon for the setting in general and the Sororitas in particular.

I did some research when I wrote this up, so I know of some of the side effects including the smoke and the toxic shock. The phosphor being hard to put out is a very tricky subject, as I'm not sure how tough it should be for a player character. Do you think the additional -10 penalty on top of the -20 you already get for the Agility Test to put out the fire is enough to represent it? And if you think the damage is too low, what would you change, keeping in mind that this should not be worlds apart from a normal fire bomb (as accurate as that would be in real life)?

Whilst I generally try to make this as close to the real thing as I can, I also intend to preserve two things I deem important:

• I cannot make it too powerful in terms of the system
  (it's a game after all - same problem as with plasma hits to the head)
• I cannot make it too complicated by adding a dozen or so special qualities / extra rules
  (this is what, so far, kept me from adding a "poisoned" effect to it)

So, if you (or anyone else, for that matter) have advice on how I might make this grenade "fit" better or simplify how it works, I appreciate any kind of suggestions!

It's a nice addition to the arsenals of 40k, and it fits well into Imperial doctrine.

That said I would not use these unless you have already house-ruled the Fire Bomb which has an incredible penetration at such low cost.

If they are nerfed however it is good to have some militairy-quality WP grenades.

Your rules might work but seems a bit outside the mold so to speak.. is it necessary to invent a new weapon quality just for one weapon?

Let me see if I can make some of my own:

WP grenades: cost 60 T (or more). Blast 3, Felling 1, Smoke.

Availability: Very Rare (Rare in War Zones).

Damage 1d10+5 Pen 6

Description: White Phosphorus are commonly employed as smoke cover or to flush out enemies in cover. These projectiles contain a substance that ignites in air when bursting, and the extremely high temperature creates almost instantly a thick, white smoke. Any target within the Blast area must test agility or catch on fire. Also, the area continues to burn for 1d5 rounds after detonation, so anyone inside it must continue to test agility or catch fire, until the flames die out. Due to the exceptional grade of fuel, a victim caught on fire by WP takes an additional 4 damage each round until extinguished.

From Deathwatch:

Smoke: 3d10 meter diamter for 2d10 rounds, or less in adverse weather conditions.

Felling: Allows the weapon to ignore x levels of Unnatural Toughness. Felling 1 thus makes an Ork's TB to become normal (4) and thus quite burnable .

So to sum it up, the damage is much better than Fire Bombs since WP burns with a much higher temperature than napalm/promethium and especially ethanol/gasoline. The damage is still not really higher than Frag grenades (2d10), but is more predictable and unlikely to leave anyone unscathed. Also the burning effect is more potent against creatures with Unnatural Toughness, such as Orks and Slaught (and Space Marines). It wil also burn through most armors, Carapace and below is essentially worthless.

Note that these grenades should not be readily available for anyone except high-ranking acolytes, Inqusitors, Munitorum and Adeptus Astartes. They are generally not sold on the black market even in major cities, and are considered too dangerous for standard issue to IG.

Here is some RL info about the real thing: http://www.globalsecurity.org/military/systems/munitions/m15.htm

Friend of the Dork said:

Not yet, but given that I've read forum posts about Ross considering to lower the fire bomb's penetration to 0 (which seems much more fitting) I was already working under this assumption. Not sure how our GM thinks about it, but I think he'd go with it, too.

Friend of the Dork said:

It's not a very elegant solution, but I felt something that negates TB would be more fitting than a higher penetration. I had also hoped that it would qualify for more than just this grenade, hence I kept its wording deliberately dubious to make it fit to anything that eats through flesh. That said, I did not know about the Felling quality yet (due to not having DW - makes you wish FFG would keep an up-to-date list of this stuff on the website for everyone to see), which, although not being quite as lethal as a flat 50% TB for everyone, sounds good! Thanks a lot for suggesting this and providing this official trait.

Friend of the Dork said:

Do you think the high penetration is good? I realize that phosphor burns incredibly hot, but at the same time I consider the armour of this era to be very effective and I don't want this grenade to become more of an anti-tank device than anti-personnel. I'd lean more towards a pen of 2-3 but maybe give it a higher Felling rating. Primitive armour (fur, leather, medieval plate) would still need to be 4-6 to even negate some of the damage, which sound fitting.

To take a Space Marine as an example, the globs should just bounce off his power armour completely harmless most of the time, but if you roll real lucky and one of them burns through the joints it should hurt even him.

As to a potentially higher Felling rating, would that make sense? Off the top of your head, what kind of beings have more than one level of Unnatural Toughness? I suppose I would find something in Creatures Anathema ... some Tyranids I guess?

Friend of the Dork said:

A viable alternative to the Proven trait, I suppose. No additional penalty for trying to put out the fire, though? Of course, given how lethal being set ablaze is, I guess it shouldn't be made too hard to extinguish it...

Friend of the Dork said:

Hm. I see the value in sticking to the basic rule for smoke, but I think I'll stick to the smaller area. Producing a smoke screen is not the primary function of this grenade, merely a beneficial side-effect. Also, it fits well to the real life equivalent.

Friend of the Dork said:

Good point, I'll copy your suggestion for the Availability rating!

Friend of the Dork said:

That was actually one of the websites I stumbled upon, too. Well, that one and the wikipedia article.

Thanks for the extensive feedback!

I Think Pen 6 is not a bad idea. Sure some of the Armour is good in 40k, but come is archaic. 6 wont really do to much to power armour, after a few play tests maybe go as low as pen 4. Felling (1) I could see too. Either way a decent right up and a worthy and common war zone weapon.

New effect description:

Any target in the blast area must test Agility or be hit. The phosphor globs will burn hot for 5 rounds, blanketing the area in smoke and forcing anyone moving through it to make a Routine (+20) Agility Test to avoid making contact. Depending on the Game Master's decision, the environment itself may be set ablaze, causing further hazards as per the normal rules for open fires.

Characters hit by this weapon will suffer 1d10+3 Energy damage (not negated by armour) per round as the phosphor eats through their body. Gobs absorbed this way will be burnt up at the same time the area effects cease to apply. Attempts to extinguish the phosphor sooner are Very Hard (-30 Agi).

Range: SBx3
Damage: 1d10+5E
Penetration: 3
Weight: 0.5kg
Cost: 60
Availability: Very Rare (Rare in Warzones)

Special Traits

• Blast (4m radius)
• Smoke (duration equal to burn time, limited to 2x Blast Area)
• Felling (damage ignores 1 level of Unnatural Toughness)
• Proven (minimum of 3 on all damage dice)

-

Changes:

• increased blast radius by +1
• increased penetration by +1
• increased damage over time
• increased rarity
• set a stable burn time for the area and damage over time effects (5)
• changed custom weapon quality for official trait ("Felling")

In addition to the initial damage (an average of 10.5 Pen3 ... more than Frag), this grenade will now do an average of 9.5 wounds over a set duration of 5 rounds to any character hit by the device itself. A single Agility test will now decide over whether the Damage over Time effect will apply (instead of the 2 Tests of the normal Flame rules). Attempts to stop the DoT effect suffer an additional -10 penalty. In addition to this its damage is increased by +3 over ordinary fire.

An average character with a Toughness Bonus of 4 (which, thanks to the Felling quality of this weapon, now includes Orks) will suffer a total of 27.5 wounds on average, 10 wounds minimum and 45 wounds maximum from the DoT effect, should he not be able to stop it.

Lethal. But hopefully balanced? Or am I still being too generous?

Make it 1d10+5 each round for DoT, and we got a deal lady. (makes it easier to keep constant damage all around)

The Very rare avail. makes it 'balanced' for me at least: no crates and crates of that at every PDF/Arbitrator/Imperial guard depots

I think it's pretty good where it is. Basically, if you toss it into a crowd of mooks it should kill or incapacitate virtually all of them. The chance of catching on fire, DoT, and Felling make it quite dangerous to tougher targets, but not overpowering.

Someone should try running some playtests, thats one of the few ways to get real good data on this kind of stuff. See if it trivializes encounters or not.

As for the Penetration issue, I think it should be left low. Already there are too many weapons which essentially invalidate anything short of Power Armor, and that bothers me.

If anything, a different device could be constructed, not a "grenade" in the standard sense of AoE but a single target thrown weapon which bursts open to cover the target in a layer of phosphorous.

The only problem I see with this: it's still a grenade delivery system, so defense should be a Dodge not Agility test.

Otherwise, very well done!

Braddoc said:

At Last Forgot said:

At Last Forgot said:

At Last Forgot said:

Your idea about a "splashing" device is interesting, too. I think this could actually be implemented into a new type of boltgun ammunition, but that'd be something for another day… If it isn’t already covered in DW, heh.

Denmar1701 said:

Denmar1701 said:

Lynata said:

All right: we'll try it 1d10+5, see how it goes: maybe a few 'test combat simulation' could help.

Braddoc said:

I'll look for a nifty picture later on. Maybe the icon from DoW:Soulstorm, or I'll photoshop a marking stripe on DH's Krak Grenade.

Oh, and I also clarified that you're not at risk from stepping into burning phosphor if you remain still after that thing exploded. Common sense, I suppose, but better to make it clear right away.

Argh it seems the machine spirit is weak.. I need an engineseer!

Friend of the Dork said:

Yeah, it is officially considered a smoke grenade, but it's a poor one as the smoke rises way too fast due to the extreme temperatures caused by this device (note that this just covers white phosphorus - some countries have instead opted to use red phosphorus which burns a lot cooler and is less lethal). I've got some suspicion that the "smoke" label on WP is primarily intended to keep this weapon from being banned under the articles of the Geneva Convention and the Convention on Certain Conventional Weapons (use of incendiary weapons in civilian areas). The Imperium can be more honest in this regard, I suppose.

You could say that the smoke screen produced by the Phosphor Grenade is more reliable (representing the higher quantity of smoke produced by WP) but at the same time limited in its maximum cover area (representing the quick vertical dispersion rate of smoke produced by WP). Essentially, the smoke screen is very thick in the middle, but as most of it simply climbs into the air you may consider using proper (standard) DH smoke grenades for a greater effect.

Feel free to tweak any of the stats, should you end up employing this device in any of your games, though! I admit the primary reason for minimizing its screening ability was to not "ursurp" the traditional smoke grenade's function. Perhaps it would be nice if "Smoke" would have a similar modifier as qualities such as "Blast" or "Felling" in the official rules instead of a fixed value.

I'm feeling with you!

I can recommend a good explanation on how to work with this forum's machine spirit, though. Go to this thread , scroll down to post #34 and enjoy enlightenment! N0-1_H3r3's explanation has allowed me to operate it with much greater reliability.

The US Armored Cav uses red phosphorous in the bradleys and m113s. Red phosphorous is not really any kind of incendiary, but as an inhalent it can be lethal. The only type of white phosphorous I can think that is used primarily for smoke purposes only,is the 203 shell known as a star cluster, which is ment to explode in the air. I think 120mm illuminators use white phosphorous also along with other chemicals. Another common use of WP is for countermeasures against heat seeking technology, typically seen on aircraft.

Lynata said:

The Spirit is willing, but the Flesh is weak! I tried, but it's tricky.