I've used Galv's Magic Shards to create a Rune System for my game Clarity's Edge. The Plugin is simply amazing, I love what it has allowed me to do. I've even gone as far as making a full suite of custom graphics for it. But I'll elaborate on mechanics because that's what we're here for.
There are a few different types of Runes and different characters are limited as far as what types they can use. I've integrated it into Yanfly's Skill Learning System so that you can purchase additional Rune slots to a maximum of 15 with JP (I call it AP in my game but it's his JP Plugin I'm using).
Runes of the same element Link when they are next to each other granting additional Skills, that way you can have equipping two of the same Rune grant you another Skill.
Example: Fire1Rune+Fire1Rune gets you Fire 1 and Fire 2. Fire1Rune+BlazeRune would get you Fire 1, Fire 3, and Fire 4. BlazeRune+BlazeRune would get you Fire 4 and Fire 5. If you set it up Fire1Rune+Fire1Rune+BlazeRune+BlazeRune, you would get all 5 Fire Spells for the cost of only 4 Rune Slots.
I've also made a ton of Links for Melee so that they can link Melee Strike Runes with some Elemental Runes to gain powerful Elemental Strikes, and done some similar things with Status Affecting Runes, Healing Runes, and Tanking Runes.
And once you have 15 Rune Slots, you might not want a wall of Skills, so I have Statistic Runes that you can use to gain flat or percentile bonuses to statistics as well as some special Runes like the Greed Rune that doubles gold drops from monsters and treasure chests, and the Counter Rune that makes you Counter 100% of Physical Attacks. Both of these are obviously some late game stuff, but just giving you as heavy a breakdown as I can because you can do soooo much with the Magic Shards Plugin.
Basically, the Rune System and how you Link them is the Magic System (and kind of a nifty puzzle of attaining skills) in my game although each Character has a set of moves that only they can gain / use. I also have two main characters that have very powerful Runes that are locked onto them and grant them some crazy special moves.
I hope that my explanation helps you guys understand some of the wild stuff you can do with this Plugin. Magic Shards is an amazing Plugin, very versatile, exceptionally compatible with other Plugins, and Galv is a genius. I would love to see some other ways to utilize it, and I'd love to hear it if you guys have any ideas for cool Runes.
Have a good one,
Z