I somehow found the time to find and experiment with this kickass Materia setup:
- Master Magic
- W-Magic
- MP Absorb + Master Summon
- MP Turbo + Knights of the Round
- Master Command
- Enemy Skill
- W-Summon
- Slash-All
- Mega-All
- HP Plus
- Final Attack + Phoenix
See, what happens is, Master Magic gives you all the spells, while W-Magic lets you use two spells in one turn. The Master Command activates most commands, and a mastered Enemy Skill will give you some nice spells (Big Guard, Angel Whisper, Shadow Flare, etc.). A mastered or level 2 Slash-All will give you Flash, which can instantly kill all opponents. A mastered HP Plus should boost your characters HP up to 9999. The famous Knights of the Round causes a helluva lot of damage each time it is cast, while absorbing ridiculous amounts of MP, and you can cast it twice with the W-Summon enabled. The Final Attack-Phoenix combo protects your entire party from death up to five times when mastered while dealing Fire damage to all opponents. Its pretty sick.