Shin Megami Tensei: Persona 3 FES

First I'll list her pattern :
Surt> Jack Frost> Thor> Chuculainn> Metatron (?sorry i forgot)> Alice> Nebiros> Masakado> Surt>....
Now her attack : Maragidyne> MaBufudyne> MaZiodyne> MaGarudyne> Mahamaon> Mamudoon> Ailments> 9999Megidolaon> Maragidyne>....
During those turns she will sometimes Attack Physically
Now the strategy :
WARNING : Do NOT use a persona that drain/null/repel her attack at any turn.
Do NOT equip ANY equipment that null/repel/drain her Attack
Persona that strong against her attack on each turn is advised.
Helel AND Satan are mandatory for Armageddon.
Equip whatever persona you bring in order to fight her with High Counter and especially for Nebiros's turn > Unshaken Will AND Null Poison.
Use a Calculator(To count damage done) and Attack her [(Without Armageddon), most preferable a top-tier element with Amp AND Boost, She resists Almighty so Black Viper is NOT advised.] until her Hp just a bit above 10000 and WAIT for High counter to kicks in and once her Hp below 10000 use Armageddon.
If by any chance she heals you might want to reset, since she will randomly cast 9999Megidolaon and Diarahan.

Note: This is a Strategy without using Orpheus Telos and this is currently the only method works for me.