Area Effect

:see also Variable, Area of effect
Area Effect is an enhancement described in the Basic Setpg 102. Although initially less than Increased Range, it eventually becomes better because of exponential (doubling) increase per 50% instead of 10x (linear) per 30%. The first level (2y) was initially set at +50% but later a half-level of 1y for 25% was allowed.
B413 describes rules, for example:
*uses the Large-Area Injury rule unless the victim is so big that only a single body part is contained within the area.
**B400 also clarifies "Don’t modify large-area injury for hit location (that is, treat it as a torso hit) unless only one location is exposed."
P100 introduces an interaction with Costs Fatigue
==hexes==
1y range is 1 hex, 2y range is 1+6=7 hexes, see discussions below
==examples==
GURPS Power-Ups 4 pg 4 "Aura of Power" gives example of Affliction enhanced with Area Effect having the Melee Attack limitation and the Aura enhancement.
==combination with Melee Attack==
see 2010 post below
==quotes from Kromm==
2010 http://forums.sjgames.com/showpost.php?p=1005332&postcount=3
:if the attacker's SM is seven or more greater than the defender's, his melee attacks inflict large-area injury anyway. See the second paragraph of Large-Area Injury (p. B400). If I were adding detail to that rule (and currently, that's all there is!), I'd look up (attacker's SM)-11 on the Size and Speed/Range Table (p. B550) and use the linear measurement as the radius of an area effect. For instance, a human (SM 0) would look up SM -11, get 1", and punch all the bugs in a circle 1" in radius; that's a fair approximation. A critter big enough to do large-area injury to a human would have SM +7; it would look up SM -4, get 1.5', and attack everything in a single hex. To affect two rings of hexes would require SM +10.
2013 http://forums.sjgames.com/showpost.php?p=1573226&postcount=37
:Area Effect is very often dependent on enablers. For instance, you can't just slap it on Damage Resistance to create a force field; you need Affects Others and Force Field first.
==quotes from PK==
===re equality===
http://forums.sjgames.com/showpost.php?p=1735159&postcount=4 9 march 2014
:Area Effect means that every target in the area is affected equally.
:(If you don't want that, add Dissipation.)
:So the combo of Area Effect + Emanation + Malediction 1 means you affect everyone within X yards of yourself at no range penalty.
:And no, there's no reason to go beyond Malediction 1.
PK's implication of using Emanation -20% here was contradicted March 2012 by PU4p4 where he instead uses Melee Attack -30% as a means of getting Aura.
Without aura the primary 20/30 difference would be:
*Melee Attack requires a roll to hit, so it can miss. The effect of a melee AE "missing" isn't entirely clear though.
*Melee Attack can parry
*Emanation uses Ready instead of Attack as of Powers
*Emanation doesn't hit self (but you get this if you have Selective Area)
The problem is largely that Malediction and Emanation and Melee Attack and Cone are all designed as solitary add-ons to standard ranged attacks, none were designed to work together
===re Aura===
http://forums.sjgames.com/showpost.php?p=1037048&postcount=17
:Aura + Area Effect means that the ability keeps firing off every second. That means that every person in the area has to make a HT roll every second until affected.
===Advantages v Abilities===
http://forums.sjgames.com/showpost.php?p=2078172&postcount=10
:The rule on p. 100 is for advantages with a fatigue cost, not abilities.
:An "advantage" is a single standalone trait;
:an "ability" is an advantage (or multiple connected advantages) after applying all enhancements and limitations.
:The Mind Control advantage does not have a fatigue cost. So regardless of what modifiers you add to it, the first bullet on p. 100 does not apply to it.
:Mind Control (Area Effect, 8 yards; Costs Fatigue, 1 FP) would cost 1 FP to use, not 8.
:You have designed it so that the ability costs 1 FP, but that doesn't mean that the underlying advantage does.
===Leech without Ranged===
re Leech with Malediction instead of Ranged in http://forums.sjgames.com/showthread.php?t=18445
:you'll also need to add Malediction. The concept behind Leech is that you are limited by (A) having to make contact with a person and hold onto them tightly or (B) having to win a Quick Contest against them. Since you have given your ability range (via AE instead of Ranged, which I think is certainly fair), you'll need to also add Malediction.
also mentions cumulative penalty:
:an ability which steals from everyone around him simultaneously, at a penalty to the roll equal to the number of subjects minus 1 (e.g., if there are four people around, the Malediction Leech roll would be his Will-3 versus their Wills.)
:Add Independent, +70%, if you want to avoid this penalty.
This is probably based on the "multiple instances" rule on Powers
===Tactical Combat===
http://forums.sjgames.com/showpost.php?p=962128&postcount=2
:Area Effect 1 is a 2-yard radius, not 1-yard.
:A 1-yard radius would be your hex in Tactical Combat, yes.
:(TC basically rounds AOE down.)
http://forums.sjgames.com/showpost.php?p=962242&postcount=7
:Tactical Combat rules effectively reduce all radii by 0.5. If you have a "2-yard radius" effect in Basic Combat, it extends two yards out. But in Tactical Combat, it only fills two circles of hexes, for what is technically a 1.5-yard radius. The assumption is that the extra 1/2-yard "spillover" into the next circle of hexes is easily and automatically avoided, since GURPS' granularity doesn't allow you to specify exactly where a person is standing in his hex.
===Half levels===
http://forums.sjgames.com/showpost.php?p=962128&postcount=2
:half-levels of AE aren't exactly canonical*, but are certainly reasonable, for +25%. "AE 1/2" would be a 1-yard radius by itself, or it would multiply the AE radius by 1.5 otherwise. 
:* I did use one in DF5 without much affair -- the Insect Swarm has AE of 1 yard for +25% on its Toxic Attack. So I guess there's even a RAW precedent if you're willing to call DF "RAW". :)
Insect Swarm can be found on page 9 of Dungeon Fantasy 5 Allies. PK refers to:
:Area Effect, 1 yard, +25%
http://forums.sjgames.com/showpost.php?p=1161448&postcount=6
:RAW is that you charge for the next level.
:Having said that, the precedent in GURPS is that when you have an base-2 exponential ability (that is, having level X gives you 2^X effectiveness), any "half levels" multiply your total by 1.5.
:In other words, if "three levels of Area Effect" (+150%) gives you an 8-yard radius, then "three and a half levels of Area Effect' (+175%) would give you a 12-yard radius. So I'd use something like this:
:+25% = 1 yard
:+50% = 2 yards
:+75% = 3 yards
:+100% = 4 yards
:+125% = 6 yards
:+150% = 8 yards
:+175% = 12 yards
:+200% = 16 yards
:+225% = 24 yards
:+250% = 32 yards
:...and so on, with every +50% doubling the radius, cumulatively.
===other===
re dodging the radius http://forums.sjgames.com/showthread.php?t=157899 and http://forums.sjgames.com/showthread.php?t=155583
==see also==
*Bombardment
*Emanation
*Large Area Injury
*Movable Area (ie Homing and Mobile)
==References==
Category:Enhancements