*Experimental, apparently I can't type.

AKA All Agility, all of the time.

This is an experiment.
It may not work as well with less mythics or pets with less base stats.
For this build you need either two light pets or two light and one shadow tank, at the very least the tank needs good gear and all points put into agility to receive the highest possible mitigation, as shown here:

http://www.sylestia.com/view/pets/?petid=801831
(starting stats at level 0: ~1400 health 100 strength, 100 intelligence, 100 dexterity, 100 agility)

Now all I did was run the entire level 50 arena bracket with some minor mistakes and spammed fairy lights - I did this with very nearly the best equipment possible and very very good starting stats on my pets, I'm not sure how effective it is with legendaries and less overbred pets.

I've found for me I could end all fights with 98, 99, or 100% health on all pets, although with some mistakes it was less. I gave all bosses at least one try and did very well, but the fights do go more slowly.

If anyone would like to comment or help out with their own experiences with this build I would be interested to hear from you.

Ping me.

Even though pure agil would seem like an easy one to pull off, even with my boosted lupora, it didn't turn out well. The arena battles require fairly rounded sylesty, to be victorious.

I am going to have to disagree with you at least so far, Oog. I am trying out Zar's method.
Just doing the level 50 arena for the first time, and this is my result fighting Mamosa with an AG based team -

http://tinypic.com/r/net9o4/8

I did not use my heal, nor rotate my pets. Not once.

I'd have to say that Zar is on to something. Two pets at 100% HP and 1 at 95%. I'd say that's not too bad.

I'll also have to disagree with you about the well rounded pets. Also, you are using LUPORAS. which, as a default, generally have lower stats than a fabled.

I haven't reached level 50 bracket yet, though I'll be trying to do that later. An all-health build is also pretty effective.

True, in general, they have lower stats than fabled... but fabled got nothing on my Lupora. :P
Tinkered with an agil build. I'm not saying it doesn't work, it's just not a particular build I can stand.