I would love to see your Barbs. 

HP: Flexible for non healer/revivers, once you start pushing 20/21 you'll likely want them in Regen+Immortal when possible, 60k HP, 3k DEF.

Speed: 150+ fine for non healers/revivers, easily 200+ for healers/revivers.

Accuracy: Need to hit 225 minimum, I believe. Been a minute. 

If you can overbuild Scyl then she will just trivialize Barbs. If not, I think you might have a rough time. Making HK incredibly fast and taking all the turns would also help.

Thank you, my HP numbers are nowhere near where they should be and I'm surprised I made it as high as I did. I typically go for stats over sets so that's why there are so many broken sets. I think I could overbuild Scyl and keep her in relentless however. Here are the 4 (again, still building Valla):

i

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Overbuilding Scyl towards the end of FW is pretty much a must, unless you've got top tier champs. I used a group of 50s and a 40 HK with an overbuilt Scyl, having her at those types of stats will just make the job a lot easier. won't be the fastest runs, but will get you to 3*'s. 

Do you have any other Barbs available?

you might want to retool soulbond a bit. she should work as is, but she doesn't need more than 75% crit rate and dropping the excess would let you improve either her damage output or survivability as you prefer.

Good call on her Crit rate, I just read her skills more closely and I can see that now. Thank you!

I have Alika, Aina, and Kallia as sort of "back up" champs whom I haven't built at all. I figured Alika can be a great damage dealer but I already have enough of those. Maybe Marked or Shieldguard could be helpful at level 50?

Completely forgot that I have Djamarsa but haven't built her yet.