Materia - Best Use Cases across FF, and How You'd Like to See it in XIV

[Shurrikhan]

Two questions for you all:

1. What's the best use you feel any FF game has made of Materia or similar features (be they power-granting, skill-unlocking, or consumable)? What did it do, and how did it feel in that game? (And, if could have been improved further there, how so?)

2. Assume XIV's concept of Materia is entirely scrapped. How then would you like to see Materia, in however wild or different a form as you like, added to XIV? (If XIV's current Materia feels bloated to you, but nothing like Materia --or, say, IX's Ability / AP system or VIII's Junction system, etc.-- would seem to fit, what other means of customization might you like for the game?)