This reminds me of a simpler time, when THMs were using spells like scourge and DoTs as opposed to three spells....ah the glory days...
Being serious though Id say that its just an extension of magic in general. Sticking a term to it only makes it more complicated than it needs to be. As an example of what I mean, white and black magic are said more than once to have the same roots and the like. Im assuming this is one of those "other branches" of magic that either aren't officially named or is just really powerful versions of already existing spells.
I mean, so far if we are looking at magic feats, we know that we can summon primals with more than just crystals, we can summon our OWN personal primals for around 200 crystals or so(bite me it happened its canon. COME AT ME BROS), and we can sort of turn people that are still leaving into voidsent. There are a number of other odd examples but this is just to help my point.
As far as the demon wall tidbit...I thought they were just giving a callback to FFXII or some such. If I had to guess just WHAT it was Id say a demon either put under contract or enthralled once half summoned into a wall to be a guardian. Im starting to go off on a rant here so I'll just end my stuff here.
TL;DR: Its probably regular magic with extra stuff we don't know about yet. Conditions and standards type of thing.
Being serious though Id say that its just an extension of magic in general. Sticking a term to it only makes it more complicated than it needs to be. As an example of what I mean, white and black magic are said more than once to have the same roots and the like. Im assuming this is one of those "other branches" of magic that either aren't officially named or is just really powerful versions of already existing spells.
I mean, so far if we are looking at magic feats, we know that we can summon primals with more than just crystals, we can summon our OWN personal primals for around 200 crystals or so(bite me it happened its canon. COME AT ME BROS), and we can sort of turn people that are still leaving into voidsent. There are a number of other odd examples but this is just to help my point.
As far as the demon wall tidbit...I thought they were just giving a callback to FFXII or some such. If I had to guess just WHAT it was Id say a demon either put under contract or enthralled once half summoned into a wall to be a guardian. Im starting to go off on a rant here so I'll just end my stuff here.
TL;DR: Its probably regular magic with extra stuff we don't know about yet. Conditions and standards type of thing.