This fight can be an absolute pain if you enter it ill equipped as Yelena is equipped with some hugely damaging moves but there are a number of other strange factors.
Her main attacks comprise of standing back and shooting at you with her machine pistol, and running at you and launching a Typhoon. Oh and don’t try a takedown on her, it’s instant death.
It’s recommended that you either have jump or EMP shielding enhancements as well as if her grenades hit the generators it will electrify the entire arena. Jump allows you to avoid pain, EMP shielding actually lets you take advantage of it.
If you need ammo or weapons:
There are lockers standing at the walls in the four ‘gap’ around the room, they contain everything from Typhoon ammo to Revolver shots and EMP mines.
Taking her out
First thing’s first, run left as Yelena is about to try and blow you to kingdom come. Ignore the first locker, pass the exit door, and then loot the second for EMP mines and some ammo.
Time to set the trap, pop down a pair of mines remembering where you put them and wait, we want to hear Eliza alert us to an incoming attack, she will say something to the extent of ‘here she comes’ or ‘watch out Adam’. When you hear those words, watch your radar.
If Yelena is going to stun herself, wait then attack. If not, try and plug a few shots into her before running away. It is possible to run right past her and avoid the explosives as well.
Once she attacks turn around, pop a few shots off, rinse and repeat trying to stun her with emp mines and grenades at any and every opportunity for easy damage.
If you have EMP shielding then this fight is much easier. When her assault is telegraphed make sure you’re waiting near one of the room’s glowing blue generators, smash it with your weapons when Yelena is close, thus stunning her, then plug the rest of your current magazine into her face.