1/2D

1/2D or ½D is a property of ranged attacks.
*B35 lists it for Affliction (advantage), where targets beyond it get a bonus to save
*B40 mentions it for Binding
*B61 mentions it for Innate Attack
*B72 mentions it for Obscure with a Ranged enhancement
*B92 mentions it for Telekinesis throwing
*B106 mentions it for Guided / Homing where it determines speed
*B106 mentions Increased Range increases both it and Max, and that it is half cost to just increase 1
*B106 also mentions it for Jet and Link and Malediction:
**Jet's is 5
**1/2D must be identical to have a single attack roll for Link
**Malediction lacks 1/2D
*B107 mentions under Ranged
*B112 mentions under Melee Attack and Emanation:
**Melee attack explicitly lacks it
**Emanation has "no range" and presumably also lacks it
*B115 mentions that Reduced Range can reduce 1/2D at half cost, but cannot decrease Max independently
*B244 mentions for Lightning
==Campaigns==
B378 "Half Damage (1/2D) for Ranged Weapons" mentions:
:"The damage of an attack modified with Follow-Up (p. 105) is never halved"
*The damage of an attack modified with Follow-Up (p. 105) is never halved, either – although its “carrier” attack is subject to 1/2D effects as usual.
:Finally, if an attack has a 1/2D range but requires a resistance roll to avoid an affliction of some sort, add +3 to the resistance roll instead of halving damage (if any).
==Walls==
Wall of Thorns (Pyramid 3-50 Dungeon Fantasy II pg 15) uses Increased 1/2D on both the Crushing (rigid) and Impaling (permeable) aspects.
==Discussions==
29 March 2009 in http://forums.sjgames.com/showpost.php?p=763857&postcount=9 "Not another shrubbery" claimed:
:Cones, as a type of area effect, do not have a 1/2D range.
It is unclear where this idea that Area Effect or Cone removes 1/2D comes from, as neither enhancement states this.
Although B378 says "Some ranged weapons (e.g., grenades) do not suffer a reduction in damage; these do not list a 1/2D range." this could simply reflect buying Increased Range only for 1/2D.
413-414 discusses reduced damage with distance for these via the Dissipation limitation but does not explicitly exclude stacking this with the halving from 1/2D.
==Examples==
GURPS Ultra-Tech:
*pg 121 "Microwave Disruptor" a "ranged cone" attack with 1/2D
*pg 122 "Neural Disruptor" same
*pg 125 "Sonic Nauseators" a cone attack with 1/2D (+3 beyond)
In 2013 sir pudding claimed in http://forums.sjgames.com/showthread.php?p=1565825
:Lots of published cone attacks have 1/2D ranges. The Dragon-Blooded's firebreath does for sure. I believe the Sonic Screamer does as well. 
GURPS Dungeon Fantasy 3 (The Next Level) page 20 actually lists "Burning Attack 1d (Jet, +0%)" and the word Cone does not appear. Nor is the Sonic Screamer a cone attack (pudding probably was remembering the Nauseator)
He also refers to Kromm supporting that there is a 1/2D earlier in the thread. URL needed for that post to confirm.
==See also==
*Max
*Acc
*RoF
*Shots
*Recoil
Category:Rules