Aura (enhancement)

Cost: +80%
==Examples==
*Burning Attack 1d (Always On, -40%; Aura, +80%; Melee Attack, Reach C, -30%) [6]
*Innate Attack (Field): Aura (+80%), Always On (-40%), and Melee Attack (-30%)
==breakdown==
Requires but does not include Melee Attack, so if you included that, the net effect is like +50.
It does appear to include Cannot Parry (normally -5%) though so the net effect is more like +35%.
==activation time==
P154 clarifies:
:The only switchable abilities activated or deactivated with a free action are Mind Shield, attacks with Aura, and switchable advantages that work instantaneously thanks to Reduced Time. The user must switch these on or off at the start of his turn."
==interaction with TET==
29 December 2018 Arringar on Reddit pointed out that Pyramid 3/19 had an example (also in Dungeon Fantasy Collected) applying Takes Extra Time to an Aura ability.
This refers to 'Aura of Power' on page 4, which eventually made it into GURPS Power-Ups 4: Enhancements also on page 4.
==interaction with AE==
:this was added in 2009 sometime between April 14th and May 1st
http://www.sjgames.com/gurps/faq/FAQ4-5.html#SS5.2.8 discusses as a "free attack" effect and stacking Area Effect on this
:An actual radius would amount to adding Area Effect on top of it all. That might not be "canon," but it's logical and the simplest way to do it.
This appears to be derived from a 24 August 2006 PM that transmetahuman mentioned on 12 December 2006:
:Powers states that an always-on damage field requires Aura (+80%), Always On (-40%), and Melee Attack (-30%). That's a range 0, "if I touch you or you touch me" type of thing. An actual radius would amount to adding Area Effect on top of it all. That might not be "canon," but it's logical and the simplest way to do it. So a 4-yard field would add Area Effect 2 (+100%) and the net modifier would be +110%. I don't see any conflicts: Aura covers the "free attack" effect, Always On addresses the "constant effect" angle, Melee Attack takes care of the "ground zero is at range zero" element, and Area Effect handles the "blankets an area" aspect. You can omit Always On -- for a net +150% -- if you want it to work like an ordinary Aura that you can switch on and off. The other aspects don't seem negotiable.
However, this in turn appears to resemble a post that TMH made a month before receiving the PM on 31 July 2006:
: By the book, an Aura has no Area Effect associated with it, so Selective Area is meaningless. I guess a GM could let someone use the same cost for a variant enhancement that let you select among those you're in contact with, without having to turn the Aura off and on, but that would be outside the bounds of what the book says.
:Likewise, the GM could let you take Aura and Area Effect (and either Melee Attack (to fit the wording of Aura), or Emanation (which I think is more appropriate for Area Effect) to make a continuing field around you that affects anyone who comes within x yards of you. Again, the books don't address that. 
The "might not be" turned out to be "is" because this was canonically used in Aura of Power:
*May 2010 Pyramid 3/19 page 4-
*March 2012 Power-Ups 4 page 4
==Supers==
GURPS Supers page 44 has Electrogenesis as an example where Aura is applied to Create.
==Quotes==
===PK quotes===
2006 http://forums.sjgames.com/showpost.php?p=195927&postcount=15
:Aura turns your transient attack ability into a switchable one. Aura is a requirement for Always On because you cannot take Always On on a transient ability, only a switchable one.
:Aura by itself does not reduce your range, but it is incompatible with any sort of normal ranged attack, and thus requires the Melee (or, one would assume, Emanation) limitation.
:if you want a character whose firey aura fills up the two yards around him, I would buy it as Aura, Area Effect 2 yards, and Emanation
2006 further http://forums.sjgames.com/showpost.php?p=195996&postcount=19
:If you're going to use Area Effect with Aura, it's my opinion as a GM that you should use Emanation instead of Melee, C, because the latter is a bit of a crock.
===Kelly re Kromm===
a 2007 post http://forums.sjgames.com/showpost.php?p=411352&postcount=9
:Kromm has actually said that Area Effect is appropriate for expanding the range of an Aura.
Indicates a pre-2008 post also exists prior to the 2010 one, needs to be located
http://forums.sjgames.com/showpost.php?p=1037048&postcount=17 in 2010
: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.
===Kromm===
25 April 2019 http://forums.sjgames.com/showpost.php?p=2258357&postcount=5
Fort the sake of game balance, Aura shouldn't damage anyone more than once per turn. Otherwise, you'll get silly results in close combat. Measure "turn" from start to start: From when I start this turn until I start my next turn, a given Aura can hurt me only once, no matter what me and the person with the Aura do, either during the active part of my turn or during everything that happens afterward.
Aura (+80%) + Melee Attack (-30%) is worth +50% because it could affect all the attackers around you if they foolishly decided to swarm you in close combat. We eyeballed that as being approximately equal to Area Effect, 2 yards, +50%, which always affects an area of similar size to "my hex and all the hexes around me." 
The upsides "discourages attackers" and "requires no action" and the downsides "specific trigger condition" and "has no range" looked like a wash.
If you start adding what amounts to Rapid Fire to it, it soon gets out of whack . . . if you really want that, buy Rapid Fire and say the Aura can affect each person up to RoF times. For instance, Aura (+80%) + Melee Attack (-30%) + Rapid Fire, RoF 3 (+50%) would cost +100% and be able to affect a given enemy up to three times (say, once for you punching him and twice when he punches you twice).
==See also==
*Area Effect with Emanation is basically melee-based (range 0)
*Cyclic
*Flagrant Aura
*Persistent
*Reflexive, similar for defensive abilities
*while conscious
==References==
*Basic Set p 102, 262
Category:Enhancements