Guild Wars 2 - Definitive Fractal AR Guide: Which setup is best for you? by StepW

Heya! I've seen a bit of disagreement and misinformation running around on fractal AR gearing ever since the infusion rework done in the July patch. I thought it might be a good idea to eradicate any doubts on this with some number crunching! There's a TL;DR at the bottom!

So, let's establish what the problem is: with an infused backpiece and infused/attuned rings, we have a total of 18 infusion slots active at any one time in our gear. We want to know the most cost-effective spread of agony infusions among those 18 slots to reach 150 AR.

There are two viable ways of doing this:

• 8 +9 infusions, 8 +8 infusions, 2 +7 infusions - SETUP A
• 6 +9 infusions, 12 +8 infusions - SETUP B

We need a way to compare the price of crafting these infusions. Since one +x infusion is equal to two +(x - 1) infusions, I'm going to go ahead and use +7 infusions as our "currency". So, one +9 is two +8s which is four +7s. This way we can compare the expensiveness of each setup.

With that in mind:

• Setup A costs 8*4 + 8*2 + 2 *1 +7 infusions = 50 +7s
• Setup B costs 6*4 + 12*2 +7 infusions = 48 +7s

What this essentially means is that Setup A costs two more +7 infusions to craft than Setup B. At first glance, this means Setup B is cheaper, but Setup A has a couple of advantages over Setup B:

1. If you're the type to swap trinkets around characters, Setup A allows you to stuff slightly more AR into your trinkets than Setup B does. Trinkets have 10 infusion slots in total, so Setup A allows you to fill them all with eight +9s and two +8s, giving you 88 AR, whereas Setup B is limited to, at most, six +9s and 4 +8s, giving you 86 AR.
2. While you can only have 18 slots active at any one time, in reality there are more infusion slots you'll need to fill up; additional weapon slots. The weapon swap alone is an additional two infusion slots to fill, without even considering any other weapons your class can use which you bring along to fractals. Setup A allows you to fill these additional weapon slots with +7s, whereas Setup B makes you fill them with +8s. If you have a number of extra weapons to fill with agony infusions, then Setup A might be better for you. More specifically, if you have four weapon slots to fill in total (which is the case for most professions because of having two weapon sets), then both Setup A and Setup B cost exactly the same (52 +7 infusions). Any more weapon slots than that and Setup A becomes more cost effective.

A couple of additional notes:

1. If you want to invest in attribute infusions, then you're forced to use "Setup C", i.e. the [KING] setup, which is 12 +9s and 6 +7s, because those come only in +5, +7, and +9 varieties.
2. I didn't perform any calculations assuming you don't infuse the backpiece, because this kind of stuff can be a bit tough to calculate as prices of Globs of Ectoplasm and agony infusions vary. If you don't infuse the backpiece, you'll be down to 17 active slots. Abstaining from an infused backpiece and making up for it with more +9s can definitely be worth it (infusing a backpiece is super expensive!), but I personally wouldn't recommend it. Mawdrey is very cheap to infuse and Bough of Melandru comes with two infusion slots by default. Not infusing the backpiece also means you don't future-proof yourself if ArenaNet introduces new AR schemes/requirements, you're down one infusion slot if you want to use attribute infusions, you'll have one less infusion slot when swapping trinkets to another character, and you'll be forced to put +8s in your weapon slots. However, if all of that doesn't bother you, then by all means go for it.

If I ever get round to it, I might whip up a spreadsheet that considers how many weapon slots you have and whether you share trinkets among sets or not to determine which is the best setup for you, but for now this guide should keep you going.

Hope that helped!

TL;DR:

• Go for eight +9, eight +8, and two +7 if you have four or more weapon slots to fill (putting the +7s in your weapon slots, and all +9s in your trinkets).
• Go for six +9 and twelve +8 if you have less than four weapon slots to fill (putting +8s in your weapon slots and all +9s in your trinkets).
• Go for twelve +9 and six +7 if you're using attribute infusions (putting +7s in your weapon slots and ten 9s in your trinkets).
  
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