View Full Version : Electric Monkey's Underhive armoury [40k weapons]

2008-01-15, 05:44 PM
A collection of 40k weapons rules for use with Skrittiblak's system, or any other attempt to recreate 40k using d20 rules. Comments are welcome.

Variant Rules:
Cover functions as described in the d20 modern srd. However, the forty-first millennium contains plenty of weapons powerful enough that it is a real possibility for a shot to blow clean through whatever cover a character has. If an attack would have hit a character if not for cover, make a damage roll against the cover. If the damage done to the cover is at least a quarter of its hitpoints, then any damage beyond this threshold is also taken by the character. Sample materials are given below:

Material Hardness Hp per inch
Wood or equivalent (fences, improvised barricades etc.) 5 10
Masonry (stone, rockcrete, most civilian construction 8 12
Industrial metal (often plasteel – used in pipes and other metallic constructions where armour isn’t a major concern) 10 30
Duracrete – military fortifications 15 20
Armaplas – armour for large fighting vehicles, sometimes used to reinforce critical sections of a fortification 20 50
(Note to self – cross reference with weapon abilities. Antipersonnel weapons should do minimal damage to masonry or tougher materials, whereas antitank weapons should only be stopped by about a foot of duracrete –)

Some weapons, such as grenades or rockets have a blast effect. A blast damages everything within its radius, regardless of whether or not it was the original target. If a blast weapon misses, the centre of the blast is displaced 5xd10 feet from its original target in a randomly determined direction. If this places the blast out of the firer’s line of sight, then GM discretion applies.

A character who is affected by a blast weapon may attempt to make a reflex save at dc 15 for half damage. Whether he succeeds or not, he dives prone and must take a move-equivalent action to stand back up. If the character forfeits the reflex save, he must make a fortitude save at dc 15 to avoid being knocked over.

If a character has half cover or better, he suffers half damage on a failed reflex save, and no damage on a successful save, and does not count as being prone. Cover less than half cover still allows a bonus to reflex saves. Note that some blast weapons do damage by ground vibrations (like earthshaker shells) or by superheating the air (like plasma bursts). These mitigate the benefits of cover, as described in the special rules for each weapon.
Flamethrowers create a cone-shaped gout of flame that affects all objects and characters in its area of effect. A character may take a reflex save for half damage with the DC determined by the shooter’s attack roll. A character succeeding in a reflex save dives out of the path of the flame, moving the shortest distance to the edge of the area of effect and lying prone. A character or object that takes damage from a flame thrower catches on fire. At the start of each round, roll a d20 for any burning character. If the roll exceeds the extinguish DC, the flames go out, otherwise the character continues to burn and must take another damage roll. A burning character, or one adjacent to him can attempt to beat out the flames for a +2 bonus to the roll for each character helping.
Some weapons are capable of semi-automatic or fully automatic fire. In Semi-automatic mode, a weapon fires a number of shots up to the Semi-auto number, with each successive shot being at a –2 penalty to hit – the first shot has no penalty, the second –2, the third –4 and so on.

A weapon capable of fully automatic fire has a “Full auto number” indicating the number of ten round bursts that can be fired in a typical round. Firing a fully automatic weapon is a full round action, and can fit one of the three following modes:

The character designates a number of areas no greater than the full auto number of the weapon. Each area consists of three contiguous squares. The areas may overlap each other, but designating an area that is not contiguous with another counts as retargeting (see below). For each area, the player makes an attack roll. Any character within the affected area must make a reflex save against a dc equal to the result of the attack roll or suffer a hit. If the character is covered by two or more areas, he must make a reflex save against each dc, and risks being hit by each shot.
A designated area consumes ten rounds.

Suppressive fire:
Suppressive fire works like spray, only each area is only two squares and consumes 15 rounds. In the character’s turn the attack is resolved like spray. In addition, a character who is present in an affected square during his own turn must make an additional reflex save. A character who passes through multiple squares affected by suppressive fire must make a reflex save for each one. Characters who have cover need not make a reflex save unless they take an action that requires them to break cover, such as attacking a character on the shooter’s side.

A character with a fully automatic weapon may fire a long burst, consisting of 10 rounds, or two short bursts, consisting of four rounds each, for each point in the weapon’s full auto number. For each burst, the attacker makes an attack roll and scores a hit for every two points by which he beats the target’s AC, up to a maximum of the number of rounds expended in that burst. If a burst attack scores a critical hit, all rounds hit, and critical damage is scored on one hit for every two points by which the confirmation roll exceeds the target’s AC.

Retargeting Automatic/Semi-automatic fire.

Weapons which are capable of making more than one attack per round may be targeted on one or multiple opponents or areas. Targetting a different opponent or a non-contiguous area is retargeting. A character who retargets changes to his additional attack bonus. A character cannot target more enemies or areas than he has attacks. If a character has to turn more than ninety degrees to aim at the next opponent or area, then the act of turning counts as an attack, and the character is reduced to his third attack bonus and may make one attack fewer than his weapon normally allows in that round.

2008-01-15, 06:03 PM
Las Weapons:

Special rules: A Lasweapon can be fired on two power settings – regular and maximum. Maximum power gives an additional damage die, but uses five times the charge of a regular powered shot


LasCell: Both lasguns and laspistols draw power from energy cells called LasCells. A las cell weighs half a pound, and contains 100 charges. The charge remaining is indicated by a display on the cell and another on the gun. A las cell can be recharged by exposure to heat or light, although the length of time this takes is generally too long to be field practical without exposing the cell to temperatures that would damage it. A standard shot from a laspistol uses one charge, and a standard shot from a lasgun uses two.

Hotshot Cell:

A hotshot cell is a specially designed LasCell that allows a far greater quantity of energy to be discharged in a single pulse, allowing a more powerful shot. Lasguns that are not specifically designed to accept hotshot ammunition overload and fail if such ammo is used.

A hotshot cell weighs 1 lb and contains enough charge for a single hotshot las blast, doing 5d6 damage. A hotshot blast cannot be overcharged.

Hotshot Pack:

Commonly used by imperial stormtroopers, the Hotshot pack is a large energy pack that is worn as a backpack and connected to the ammo slot on a lasgun by a length of durable and flexible cabling. A hotshot pack contains enough charge for 50 shots and weighs 30lb.

Support Cell:

A support cell is a scaled up version of the LasCell for use with Lascannons and multilasers. It weighs two pounds and carries 100 charges. A single shot from a multilaser uses one charge, while a lascannon uses twenty.

Emplaced Las Weapons:

When mounted in buildings or vehicles, a heavy las weapon, such as a multilaser or lasacannon is commonly connected directly to the power grid or vehicle’s power plant, giving it an effectively unlimited supply of ammo. This is achieved by an adaptor that fits into the weapon’s ammo slot, allowing a standard infantry weapon to be used, easing the logistics associated with such weapons.

The laspistol is the standard sidearm of the imperial guard. While lacking the power of bolt weapons, its ready availability and reputation for reliability makes it popular across the galaxy as a sidearm or personal defence weapon.

Weight: 2lb damage: d6 Crit: x2 range: 50’ size: small Proficiency: Basic firearms Other: Semi-auto 3, charge selection


The lasgun may well be the most common weapon in the galaxy (with the possible exception of the ork shoota). As the standard weapon of the imperial guard and planetary defence forces, countless lasguns are produced in imperial factories every day. Many make their way to underhives and other lawless areas, where their rugged construction and extreme reliability mean fighters swear by them.

Weight:7lb damage 2d6 crit: x2 range: 250’ size: medium Proficiency: basic firearms Other: Semi-auto 3, charge selection, can be modified to take hotshot cells as well as conventional ammunition. Has bayonet lug.

Long Las:

The long las is a variant lasgun with an extended barrel containing the optics necessary to produce a fine beam that maintains coherency for greater distances than a conventional las bolt. It also comes with a magnifying scope and a fold-down bipod support.

Weight 9lb damage as ammunition range 400’ size medium Proficiency: Sniper rifles Other: +1 to hit when the sniper is settled in a firing position, -2 when not. Settling in a firing position is a full round action
The long las can use conventional ammunition, in which case it does the same damage as a lasgun and can fire with the same semi-auto characteristic. All long las rifles can also accept hotshot rounds.

Sniper weapons have a crit range 19/20 and do 3x damage on a crit.

A common anti-personnel weapon in the Imperium, the multilaser is the primary weapon of the Chimera armoured personnel carrier and is also used in numerous strongpoints and fortifications.

Weight 40lb damage 5d10 crit: x2 range 300’ size: huge proficiency: Heavy Weapons Other: FullAuto 3, Semi-auto 6. Firing is a full round action. –2 to hit if fired without proper bracing


The primary anti-tank weapon of the Imperium, the lascannon is truly devastating. Often regarded as overkill in the cramped conditions of the Underhive, where vehicles rarely operate, the lascannon is still unmatched in cracking open fortified positions and makes a mockery of any infantry armour.

Weight : 30 lb Damage 10d10 crit: x3 range 300’ size: large Proficiency: heavy weapons

Slug Throwers

Stub gun:

Stub guns are simple hand weapons, turned out in droves by underhive workshops that lack the precise machining capability for anything better. Stub guns come in many forms, but the most common resembles a six-shooter revolver from early earth history.

Weigh:2lb damage d8 Crit:x2 range 30’ size: small proficiency: Basic Firearms


A stub gun takes six cartridges, each of which weighs 1/50 lb

Auto pistol:

Although largely superseded by las weaponry, autopistols remain popular weapons for self defence and criminal activity, as they can be manufactured without the infrastructure required for laspistols, and possess an intimidating muzzle report.

Weight 2lb damage 2d4 Crit: x2 range 50’ size:small proficiency: Basic Firearms Special Semi-auto 3

An auto pistol takes a magazine holding 20 rounds. Each magazine weighs ½ lb


The autogun is the pinnacle of personal ballistic technology. Firing caseless bullets at speeds that are just subsonic, the autogun finds regular use in lawless areas which lack the manufacturing facilities for lasguns, and even in the military of lightly developed worlds

Weight 8lb damage 2d8 Crit: x2 range 200’ size: medium proficiency: Basic Firearms Special: Semi-auto 3

An autogun takes a magazine holding 30 rounds. Each magazine weighs 1lb


The design of the shotgun has changed little since the weapon was first invented, over 38000 years ago. What the 41st millennium has seen is a great range of inventiveness applied to the ammunition used for these large bore weapons, keeping them popular, particularly among the ranks of the Adeptus Arbites.

Weight: 10lb Damage: As ammunition Crit: As ammunition Range: 60’ size: medium Proficiency: basic firearms Special: See ammunition


A standard combat shotgun has an internal magazine that can be loaded with individual shells. The magazine typically holds five shells, each of which weighs 1/10 lb

Solid shot:

Each shell is a single metal slug that hits its target with a brutal impact.

Damage: 3d8 Crit x3

Scatter Shot:

Each shell is a cluster of pellets that are scattered upon impact

10’ radius blast, 2d8 damage


A manstopper shell contains a small shaped charge, for maximum lethality.

Damage 3d10 Crit x3, 5’ knockback
Executioner shells are high-tech shotgun shells favoured by the adeptus arbites. They are effectively self-guided manstopper shells.

All effects as manstopper
Special rules:
Extends range increment to 120’
+1 to hit at ranges >30’
crit range 19/20

Heavy Stubber:

The heavy stubber is a popular heavy weapon in most underhive combat due to its ease of manufacture and repair, and effectiveness against the lightly armoured fighters that are commonly encountered. The heavy stubber spews out bullets at such a rate that it practically fills the air with lead.

Weight: 20lb Damage: 3d8 Crit: X2 Range: 200’ Size: Large proficiency: Heavy weapons Special: Auto fire 2 – Cannot be fired in any other mode, Cannot be fired on the move

Ammunition: A typical heavy stubber uses an ammo drum containing 200 rounds and weighing 6lb, although variants are available. Emplaced heavy stubbers are often fed from belts of 1000 rounds or more.

The autocannon is designed to take down light vehicles. It fires fist-sized slugs of depleted uranium as fast as its smaller cousin the autogun fires bullets.

Weight: 30lb Damage:6d12 Crit:x2 Range: 300;’ Size: Large proficiency: Heavy weapons Special: Semi-auto 4, cannot be fired on the move

An typical infantry autocannon is fed rounds from a rack holding 8 cartridges. Each round weighs 1 lb, and the empty rack weighs ½ lb. Emplaced autocannon may have larger magazines.

Assault Cannon:

The assault cannon is a variant on the autocannon. Firing smaller slugs at higher velocities, and using a gatling gun arrangement to maintain its incredible rate of fire, the assault cannon can tear a squad of armoured infantry to ribbons in seconds. However, assault cannon are rarely used by infantry due to the extreme weight of the weapon and its ammo, and the weapon’s inaccuracy at range.

Weight: 40lb Damage: 6d10 Crit: x2 Range: 100’ Size: Large proficiency: Heavy weapons Special: Full auto 3, can only be fired full auto, cannot be fired on the move.

Ammo: An assault cannon is fed from a belt or drum carrying a variable number of rounds. Each round weighs 1/4 lb.

Bolt Weapons

Bolt Pistol:
A favoured weapon for the elite, every bolt pistol is meticulously hand crafted by dedicated tech-adepts. A bolt pistol is a scaled down version of the boltgun or bolter, and fires small self-propelled projectiles that explode upon impact, making it a devastating weapon, if hard to maintain and procure ammo for.

Weight: 3 lb Damage 2d8 Crit: 19-20 Range: 50’ Size: small proficiency: Basic Firearms Special: Semi-auto- 3


Bolt pistols commonly take ammunition in sickle-shaped magazines, each of which weighs ½ lb and contains 10 shells.


The boltgun is the standard personal firearm of the adeptus astartes, and requires the finest techniques to manufacture. Many boltguns are ornately designed, and so well crafted as to be considered works of art, handed down in families for generations. As such, a functional boltgun is a prized status symbol among imperial citizens.

Weight:10 lb damage: 3d8 Crit: 19-20 Range: 250’ Size: medium proficiency: Basic Firearms Special: Semi auto-3


Bolt magazine: weight 1.5lb – contents: 20 shells

Storm Bolter:

Weight:15 lb damage: 3d8 Crit: 19-20 Range: 250’ Size: medium proficiency: Basic Firearms Special: Semi auto-3, full auto –1

A storm bolter is a bulkier version of the bolter, capable of fully automatic fire. Its weight and recoil are such that it is practically a heavy weapon, used only by Space Marine terminators and on pintle mounts.

A storm bolter can hold two bolt magazines

Heavy Bolter:

While bolter technology is rare and highly prized in personal weapons, the Heavy bolter is probably the most common support weapon in the imperium. Found everywhere from fortifications, to tank sponson mounts, to squad support weapons, the heavy bolter is an effective antipersonell weapon. Less cumbersome than the multilaser, it is still capable of cutting a swathe through infantry.
Weight:30 lb damage: 4d10 Crit: 19-20 Range: 250’ Size: large proficiency: Heavy weapons Special: Semi auto-6, full auto –2

Flame Weapons:

Hand Flamer:
Weight 5lb dam d12 range 10’ cone special: flame – extinguish dc 10

1 shot uses 1/5 lb of promethium: Standard tank size 5lb – empty tank weighs ½ lb

Weight 30lb dam 3d6 range 20’cone special flame – extinguish dc 15

1 shot uses ½ lb of promethium. Standard tank size – 10lb – an empty tank weighs 1lb.

Heavy Flamer:
Weight 45 lb range 50’ dam 4d6 cone special: flame – extinguish dc 18

1 shot uses 2lb of promethium. Standard tank size 15lb – an empty tank weighs 1.5 lb.

Plasma Weapons:
Plasma weapons are expensive and highly temperamental. They are hard to find in the underhive, and it’s harder still to find someone who will repair a malfunctioning plasma gun without deciding to keep it for himself.

Plasma pistol:
Plasma gun:
Heavy Plasma gun:


Grenade Launcher:
Weight: 15 lb, range 100’

Grenade weighs 1lb

Frag Grenade
3d6 damage 25’ diameter blast, cannot crit
Krak Grenade
5d10 damage to all in target square, Halves hardness, crit X2
Missile launcher
Weight 25lb, range 150’
Rocket weighs 2lb

Frag Missile
4d6 damage, 35’ diameter blast, cannot crit
Krak Missile
6d10 damage to all in target square, Halves hardness, crit x2


Improvised armour:
Some fighters wear armour cobbled together from thick plates of scrap metal. It’s heavy, cumbersome, and easily burnt through by even the common lasgun, but sometimes it’s all you can get.
Weight: 40 lb AC +4 Max dex +2 DR 2 Skill penalty: -6

Flak armour:

Flak armour is the standard armour of the imperial guard. Widely reviled for being bulky and uncomfortable, it does at least offer basic protection against small arms.
Weight 30 lb AC +6 max dex +4, DR 5 (8 vs blast weapons) Skill penalty –2

Mesh armour:

Weight 25 lb AC +8 max dex +6 DR 7 Skill Penalty -1

Carapace armour

Weight 40 lb AC +12 max dex +2 DR 10 Skill Penalty -4

Power armour:
Power armour is almost never seen in the underhive, but is included for purposes of comparison.

Weight 60lb AC +18 max dex +6 DR 15 Skill Penalty –2

Melee weapons:

Most melee weapons are as in D&D, with upgrades as described below.

Chain Weapons:

In the tight corridors of hive cities, combat is frequently up close and brutal, and traditional melee weapons have little chance of penetrating 41st millennial armour. To give themselves an edge, many fighters carry chain-weapons – bladed weapons with rows of sharp chainsaw teeth running along the edge to grind armour and flesh.

A chain weapon deals damage as the weapon it is based on, but with an additional d6 points, and an threat range increased by one step The chain and motor adds 1lb to the weight of the weapon, and a chain weapon is powered by a 1/2lb energy cell similar in design to a lasgun cell. A cell can power a chain weapon for 50 rounds continuous use.

An unpowered chain weapon does damage as the base weapon.

Power weapons:

Power weapons are sophisticated and lethal. Generally borne only by elite Space Marine assault squads, a rare few find their way into the hands of wealthy hivers

A power weapon’s field generation unit adds 1.5 lb to the weight of the weapon.
A power weapon uses the same energy cell as a chain weapon, but can only be powered for 25 rounds.

A power weapon damages as the base weapon +2d10, and ignores half the target’s hardness. The exceptions are described below

Power Maul:

Power mauls are the favoured weapons of the adeptus arbites, and can be used to deliver a nonlethal shock to a subject.

As club with power upgrade

Special: Can deal subdual damage with no attack penalty

Power Fist:

Power fists are the preferred weapons of space marine terminators, as they allow the user to punch and tear the target directly. As such, a power fist is equipped with a larger disruption field generator.

A power fist weighs 4 lb and takes two energy cells, both of which together can power it for 25 rounds.

A power fist does 3d12 damage and ignores all of a target’s hardness.

2008-01-17, 08:07 AM
wow... just wow...

I could kiss you, I really could.

2 suggestions:

1. Plasma weapons should do flame damage, as above all else plasma is HOT. you may want to consider making the plasma cannon have a small splash, as a blob of plasma that big would likely splatter on impact, burning whatever it touches as it dissipates. It'd probably function as a Hellgun on PCP, cocaine, and black tar heroine, washed down with a bucket of peyote buttons and a shot glass of LSD in terms of damage. You'll need to refresh my memory on TT stats, but it must have some quality to off set the "Gets Hot" rule.

2. Spoiler the different weapon categories for ease of navigation.

other than that, i wish to award you +5 Internets and some Moist Cake :smallbiggrin:

2008-01-17, 05:37 PM
Thanks for the comments - and to think this all came about because I thought Laz's autocannon was underpowered. I've spoilered the descriptions as you suggested.

For tabletop rules, I'm working from 3rd? edition (the one that was around when Necromunda first came out), so I don't know about the gets hot rule. that said, plasmas in 3rd are:

plasma pistol:
max power: range 18", str 6, save -1 1 turn to recharge after firing
min power: range 12", str 4

plasma gun:
Max power: range24" str 7 save -2 1 turn to recharge, 1 sustained fire die
min power: range 16" str5 save -1

Heavy plasma:
Max power: range 72" str10 save -6 1 turn to recharge 1.5" blast
Min power: range 40" str7 save -2 1.5" blast.