Make sure she’s lvl 70. I use ancient one (L) and shuri. Shuri because she gives good defensive support as well. Don’t just face tank the boss. Play it like cable. When he’s doing beam on the right, ready to use 5 on his left side. Also don’t do 3c5. She needs to always be either in her 5 i frame or her 3 imunity. Always aware of the boss attack. Run or switch when he’s about to jump. And i switch to ancient 1 for the heal if i need it.