Empowered Curse is pretty much the only viable talent.
Spirit bombs might be useful vs a tank heavy comp with lots of shields, even then I think its worse because they can get resil.
Yakai Doll - Get 5 stacks then right click. It is worth right clicking on almost any stack level if it gets the kill.
Every time you shoot a new target it takes 2 stacks off ANYONE else with stacks. If it takes 2 or more stacks it applies an extra stack to your target.
Trick: Hold down left click even when you think no one is around it will sometimes auto attack and get you a free hit.
Savage Tear - Level 5 Essence drain card
1 Stack = 540
2 stack = 680
3 Stack = 820
4 Stack = 960
5 Stack = 1100 and disables their weapon for 1 second
Trick: because it has a very slow animation it allows you to kill them around corners, aim right at the corner they went around and it may still land.
Trick2: Right click for savage tear and don't stop holding down left click for an almost instant follow up hit if the tear didn't kill them the next hit should and its instant.
Spirit Lure - Seems kinda crap on all builds but its actually really good once you get used to it. Level 1 card to give 10% speed is really helpful. You can leave them in chokes. They are excellent as an early warning on flank points and sometimes offer an escape by reactivating back to a fight behind you. I don't recommend using them often as an engage unless you know who is coming and you lay the trap specially for them. Putting cared points on the range the fear works just isn't worth it so they won't often be feared.
Where they do shine is on pushing the cart or stopping the cart being pushed. Chuck them in the carts path and you can push back tanks.
They are also really good when contesting payload or capture points for pushing off tanks that are trying to get touch.
Body and soul - This ability kinda sucks. For me I dislike it because Kazumi works really well with high ping. I play with 200 ping so there is certain characters I can't play. Kazumi works but with ping over 150 you will get a rubberband at both the start and end of the ability and a heavy one if you reactivate to teleport back.
Anyways. This is an escape ability but you must find cover or a hiding spot first. You can use it to get past choke points. You can use it to engage through spam. For example say Skye drops a bomb on the point and you are in cover and it's at 99% overtime, stay in cover use this ability to move to the point. Bomb will go off and you will appear on the point.
It can be at high risk used as an escape if you think you can take the damage until the ability ends. It is a gamble but in some cases might work.
Bitter Betrayal - After a few seconds it explodes and gives stacks on enemies. Does a DOT and if you hit 2 people you shoot super fast 3 or more is really fast. I don't think there is much difference between 3 and 4 targets with stacks because of diminishing returns.
Best way to use this is on a tank surrounded by others, or the main target you want to kill. You don't have to shoot the person you ulted to get extra damage just shoot anyone that was hit with the ult as they will have 5 stacks. Every time you shoot a new target it takes 2 stacks off anyone with stacks. So after 3 hits no one but your target will have stacks. It might be worth not shooting in some situations like say if you got 5 stacks on everyone, their damage will be reduced. Take your time finding a good target.
Tips: Ignore tanks especially any tank with sheilds. Only go after them if no other targets.
Do not rush in. Stay back and snipe. Play her a little like Tyra. Use cover. Setup dolls so you don't get flanked.
Note the icon pictures are not correct so read the descriptions to make sure you select the correct cards. Names are correct.
Essence Drain 5 - Gives my maximum finishing power. This must be 5 always.
Betrayal 3 - This allows you to right click every 8 or so seconds. You don't need it higher as it usually takes longer than 6 seconds to apply 5 more stacks. I start chronos 1 so its 7 seconds. Chronos 2 = 6 seconds. Chronos 3 = 6 seconds so can maybe skip it.
Surrounded by fear 5 - This is another must at level 5 and is probably the best card. You start almost every fight with 2 stacks which allows you to apply the next stacks much faster.
Filler cards - You can change for paystyle
Deadly Trap 1 - you get 10% boost any time anyone goes near a lure. It's good to have a lure near you and if you retreat you almost always get 10% boost if they chase.
Blood Mist 1 - This doesn't seem like much but it can save your life or ensure someone gets feared vs not feared.
Chronos 2 is really good. If you can afford it grab it over Nimble but below is usually the order you will get it in most games. I am not sold on Chronos 3 having any effect.
Max nimble 3 is good.
Haven 2 is good. Level 3 only if you maxed everything else.
Lastly you should add in resilience and maybe even HP depending on the team comps. I don't think her ult is powerful enough to justify Moral boost. Master riding is another good item depending on map.
Your Savage Tear deals an additional 10% base damage per stack of Curse on your target.
Reduce the Cooldown of Savage Tear by 1.5s.
Surrounded by Fear
Hitting an enemy with Yokai Doll applies one extra stack of Curse once every -25s.
Decrease the Cooldown of Spirit Lure's reactivation by 0.6s.
Increase your Movement speed by 10% for 2s after one of your Spirit Lures triggers.
Reduce the Cooldown of all your abilities by 10%.
Gain 7% Movement Speed.
Reduce the Cooldown of all your abilities by 20%.
Gain 21% Movement Speed.
Reduce the Damage you take from Direct and Area of Effect attacks by 12%.
Reduce the duration and effectiveness of Crowd Control and Slows by 50%.
Increase your Mount Speed by 30%.
Your weapon shots gain +20% Lifesteal.
Zhin - Full on counter to zhin, finally. He cannot reversal the curse
Andro, Drogoz, Vatu, Evie - anyone in the air really. They are easy to hit and you can left and right click most easily while dashing. Some she is less stronger vs some of these than others. I wouldn't say OP but she can hit more easily than other chars.
Skye - You must get illuminate at least level 2 or you just can't target her at all. Level 3 is probably the best bet here.
Most tanks - especially if they have sheilds.
Very long ranged characters - like cassie etc. If they keep their distance you are basically useless.
Also deplorables are your worst nightmare for targeting.