I have mixed feelings about Endless Alchemy Candy Sea. It looks great, but it’s not very unique (there are many blue+heavy red sheen inks out there), and it sometimes has drying issues. For example, parts of the swatch were still tacky after a week. On top of that, it has a tendency to dry out pens faster than usual and gum things up, which leads to hard starts and clogs.
Scans
Scans don’t typically show much sheen, but this sheens so heavily it still makes an appearance, though not as prominently.
The scans do make it easier to see how it shades in some cases, and the areas with less ink have little to no sheen.
Video
This video was taken inside a light tent where the even light is not the best for showing off sheen, but even under these less-than-ideal conditions, it’s still easily visible.
Photos
Iroful and MD show stark differences in the sheen depending on the angle of the light. Col-o-ring is more even and less interesting, so it’s not shown here.
Microscope
Microscope photos show heavy red sheen and a much lighter cyan where less ink has settled.
Writing Samples
Writing samples also vary by light angle, here are a few photos of writing in an Endless Storyboard spiral notebook.
Chromatography

The chromatography seperates out into sort of a blue-gray, cyan, and dark blue at the leading edge.

Nothing too noteworthy under UV light.
Group Photo
A wider view of a couple swatch cards and chromatography to show them in visible light. Nothing too surprising here compared to the other images, but it does show how evenly the col-o-ring swatch sheens.

Uniqueness
I don’t think I have all that much ink in the grand scheme of things and even I have three other inks with similar properties, though one is just a sample vial:
Verdict
It has more than its share of drawbacks, but it is worth the trouble since it looks nice on the page.
As with similar problematic inks, either use a pen that seals very well, or use it fast before it can dry out and gum up the feed.
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