Here's a guide written by Xvenic on how to build your Dark Valkyrie towards PvP in the game Kritika on iOs and Android Devices.
For reader, you could say Dark Valkyrie is pale compare to CA, CrA, SM in term of many things
She's good cause many of her skill got big radius,
but then again she still lose to CA in term of Arena, and lose to SM in term of monsterwave ,
and now with CrA coming DV kinda left behind
Now, I've been trying many combination of gem built, and skill combination and it still kinda hard for her to compete.
Here's a tips to balancing the DV in Arena
Skill Build
1st slot - Fatal Delight
2nd slot - Death Trap
3rd slot - Heaven bound
4th slot - Siren's Snare
Why this skill? For DV with Fatal Delight, Hit Count top the Damage output as Fatal Delight give 100% increase of Critical Attack.
Fatal Delight
100% Crit Attack Increase? nothing more to add.. sensation delighttt
Death Trap
Usually I say death trap is a bad skill, AoE's small, High Cooldown, in term of fighting episode bosses also useless.
Then again in PvP after death trap summoned, it stays there while DV can keep attacking, unlike many of other skill.
Heaven Bound
Why default skill? in term of spam-able skill for DV there's only three - Heaven Bound, Vicious Split, Vixen Ambush with 10s CD.. if by Any chances the fight goes bellow 15s then only this three skill can be used twice. As for why Heaven Bound between this three? Like I said hit count over damage output in DV
Siren's Snare
To be exact, you can also use whiplash, but from personal opinion siren's snare hit more than whiplash, but whiplash got bigger AoE. then again 1v1 what's the use of this AoE? lol
What's the Build?
DV like I said need to crit as much as she can, but in the process of that she need to tank all the damage, so Defensive built and Crit Rate increase built are needed
As Far as Gem Built, using 2x Onyx is a must, where as equipment goes, crit rate / def are preferable
Misc: MASTER Skill?
Hate to say this, but master skill that could really helpful for Dv is Cooldown reduce... but it's kinda useless for other char especially our new char CrA..
Guide's work at least for me, so if there's a different opinion i'm sorry to hear that 
IGN: Xvenic
Server: SEA
Avatar: (Is it Set, Wings, Weapon or Body, since the thread doesn't explain much, i'll assume its a set )
Wing of Destructions Lv.30 Black + Valkamorts Luxurious blade + blade assassin vortex for Crimson Assassin
PS: by any chance it's not a set but pick one, then the priority would be wing, blade, body