When the game was first released, we saw precious little of Holomancy. It's an Asuran invention which could likely best be described as the master of magic, specifically dealing with light, to produce images. We've seen them utilize it throughout Rata Sum and their labs to project images around crafting stations, for data panels, and for grand images (like the banners of each of the three colleges).

It's also been, until recently, something solely limited to imagery. It's thus been seen as something of a dead end, a study that's already reached its primary potential, as evidenced by Elli's commentary in The Source of Orr, and had no further applications. Elli, with inspiration from Zott, was able to create a "Holo-battleframe" that gave her Hologram physical presence. It's also been demonstrated that holograms can be given physical presence in the related Splorge Metamystics Dynamic Event wherein a Progeny manages to create a "real" Dolyak out of a hologram of one.

It was Moto who continued to demonstrate that Holograms could be given physical presence with his Super Adventure Box, not only through the holographic environment, but with weapons that born from the same technology.

Dragon Bash continued the theme with projectors that created simulated Dragon Minions. The Aetherblades proceeded to steal these projectors after the revelation of their existence, and Scarlet repurposed them to create and endless supply of Holographic Pirate Minions.

The final iteration seems to be the projections Scarlet uses in the fight on the Breachmaker, where she's managed to render them immune to attacks that don't carry the same energy wavelength.

I doubt we've seen the last of the technology. I've a few Asura who are utilizing their own variances of it, themselves.