Board Thread:Suggestions/@comment-5553481-20160330135833/@comment-28043470-20160413174629

Cruggles wrote: I don't know much about Astrophysics but... For UmbraK, if there was someway we could prove either dark energy, dark matter, or dark fluid, those could be used for UmbraK. Just a possibility to bring up. Although that would require them to get past being just hypothesized.

It also depends if dark matter Absorbs enough light to make it appear like a shadow, if it doesn't interact with light at all, it'll be invisible, now there are some ways to make a "Shadow" effect Method 1. You could manipulate ferrofluid a black magnetic fluid.

Method 2. A substance called vantablack, which absorbs almost all light(over 99% but still less than 100%)

Or method 3. you could use destructive interference to cause the light in the focus area to dim.

Method 3 is still technically photoK since you are using photons that interfere with visible light but still, we could say umbraK is manipulation of photons that interfere with light we could even call these "Dark Photons"(well that's the most ironic thing  I've said today).

I know none of these are what your wanting, but I can't think of anything that exists 100% though I'm still looking for alternatives.