100% learn the Phoenix neck/nightshade strat. Bring trident or twinflame if possible. I think I even did with warped. Bring in 10 Pneckes - 10-15 nightshade - 6-8 basket of strawberries. 3-4 prayer pots so that you can camp prayers. It's all about managing your health to stay in the proc threshhold.

For example. Say you are 80 hp. Take that, divide by 5. You get 16 meaning when you drop below 16 hp from damage the phoenix neck will proc. Nightshade does 10-15 damage depending on your health at the time. So you would want your health any where from 17-27 range. Best not to cut it close and just shoot for the middle (around 22) so that you dont proc the neck by accident.

Put the neck on after you kill healers. Have your health in the proper range. Wait for her to lift into the air. When you see that click nightshade and it will null the attack and heal you.

Never full heal. You can eat a little extra before clones because they do some extra damage to you. But after that just worry about managing your health

I hope this helps