The latest edition of 40K added a powerful new weapon to the Space Marine armoury: graviton firearms. These rare weapons cause gravity to increase at the target area, crushing enemies under the weight of their own armour. Their tabletop stats are as follows:

GRAV-PISTOL Range: 12”; Strength:*; AP: 2; Special: Concussive, Graviton

GRAV-GUN Range: 18”; Strength:*; AP: 2; Special: Concussive, Graviton

‘Concussive’ reduces the target’s Initiative to 1 for a round, while ‘Graviton’ means that the ‘to wound’ roll needed equals the target’s armour save, while vehicles suffer a ‘glancing hit’ on a roll of ‘6’.

So, these are fairly short-ranged weapons, incredibly deadly against heavily-armoured opponents, but a trivial threat against lightly-armoured foes. The ‘concussive’ effect is obviously intended to represent the target being slowed to a crawl by the effects of drastically increased gravity- this can potentially be quite colorful in an rpg. Grav-Cannons are vehicle-mounted weapons which simply have loner range and higher rate of fire. I’m a little surprised that these weapons haven’t appeared in Deathwatch yet (or, if they have, I must have missed them). Here’s my attempt at adapting ‘grav’ weapons to Deathwatch :

GRAV-PISTOL Class: Exotic (Grav), Pistol; Range: 20m; RoF: 1/2/-; Damage:* I; Pen: *; Clip: 6; Rld: Full; Special: Graviton*; Wt: 6; Req: 30; Renown: Distinguished

GRAV-GUN Class: Exotic (Grav), Basic; Range: 50; RoF: 1/3/-; Damage:* I; Pen: *; Clip: 9; Rld: 2 Full; Special: Graviton*; Wt: 28; Req: 35; Renown: Famed

* Graviton- This weapon inflicts damage by increasing the effect of gravity upon the target. On a successful hit, the target takes 1d10 damage, +1d10 per Size category above Average (so, 2d10 for Hulking targets, 3d10 for Enormous, and 4d10 for Massive), up to a maximum of 4d10, plus 1 per point of Armour on the target’s Body location (therefore, a Tyranid Warrior [Enormous, 8 Armour] would take 3d10+8 damage from being hit by a graviton weapon). This damage is not reduced by armour or effected by forcefields, but Toughness applies normally.

In addition, the increased gravity has effects beyond inflicting damage. The target has a chance of dropping anything being held, as objects drastically increase in weight. An Ordinary (+10) Strength Test is required to avoid dropping an object up to 10kg, with the test difficulty increasing one step for each additional increment of10kg (hence, a 27kg Astartes plasmagun would require a Difficult [-10] Strength Test to avoid dropping). Also, the target is slowed as they struggle against the increased pull of gravity- the target suffers the effects of a ‘High Gravity World’ from the Deathwatch Rulebook , page 210, until the start of the shooter’s next turn. Finally, Flying and Hovering targets drop 1d10 meters upon being hit; if this brings them into contact with the ground, they take Falling damage as normal.

I haven’t figured out how these weapons should effect vehicles yet- I’m leaning toward some type of ‘movement damage’…

Thoughts?

Deathwatch Rites of Battle P137: "Deathwatch Graviton Cannon" (Bottom right corner of the page)

Its got two modes, spread and focused and imposes massive strength penalties on anything inside the area of effect and restricts movement plus does a little bit of damage. Doesn't affect vehicles or is not explicitly mentioned as but does allow GM creative licence.

You can use the stats on that thing as a basis to make a smaller pistol variant or a vehicle mounted at your discretion.

Deathwatch Rites of Battle P137: "Deathwatch Graviton Cannon" (Bottom right corner of the page)

D'oh! I totally missed that...

Think RT has some Graviton weapons too. maybe even main book. I was looking in one of them, at an Inquisitor with dual Conversion Beamers, and wanted to see their take on those cheesy weapons. Didn't find them immediately, but remember seeing graviton weapons.

Also see Graviton Gun in Dark Heresy - Inquisitor's Handbook p. 132