First, for a good discussion, let's have an explanatory video! (it helps people that -cough- haven't played FF6, and it helps to refresh heads and think better).
The video description even includes some especifications for the skill (second paragraph).
So, first of all, Runic has two important characteristics:
- It changes spells targets. If it is a single-target spell, that single target is set to the character using Runic. If multi, it sets user as sole and only target.
- The spell effect changes to recovering a very small amount of HP. Doesn't matters if it is Poison or Fire3, it still heals the same (~4 lol).
At that second step, yeah, you can stick some special effect depending to what skill was used or the skill element.
Sadly, anything that involves changing targets needs a script. At least from what I can think by now, you can't intercept skills by eventing at the moment of executing them. The only way I see this done with events is making all monsters have two sets of skills, one used when a specific character has Runic, one when it doesn't. Then make blank versions of each skill (a.k.a. skills that just show a name, but don't have any effect). Then you make these skills execute a common event, where you apply all your desired effects to your specific character.
Also you can make a conditional, so it searches for a character afflicted by the "Runic" status.
It's pretty tedious, but it can be done. Now with scripts... just modify the target selection method, stick a "someone has Runic?" check, change targets accordingly. Then go to the element effects method (or hopely the previous to that one). It could be good to make it execute a different set of data (effects), so it overrides the regular skill effects.
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Now, discussion! Runic, thing is not making it superpowerful, but still useful. FF6's Runic affected a reduced selection of vanilla spells. It deactivated when Celes used another command (so she stays commited to the cause!). Runic didn't healed a lot neither, it was more of a symbolic value (because if not, you could wonder where the Frick the spell went). Also it was weapon-dependent, not all blades were compatible with Runic, and Runic NEEDED a blade.
I'm by now going with a reduced version in my game, my Lightning Rod skill. I made Thunder an overpowered element, so Lightning Rod pretty much makes all Thunder skills (including your party's) useless (it also makes a symbolic MP recovery lol). I will not stick it to ANYTHING I see, but it will have some presence...
This is all I have to say by now,
Orochii Zouveleki