Color Shift: blurple/reddish pink/orangey gold
Parent Polish: Ozotic 504 (Twilight)
Other Polishes Included:
Dance Legend Celia, Enchanted Polish Octopus Garden, Ozotic 534, Darling Diva Polish Killer Queen, CrowsToes Muspelheim
Other Polishes With This Pigment: Artform/Chemistry 504, Ludurana Emocionate, Hits Dreamer, Hits Sweet Dreams (holo), ILNP Cygnus Loop (regular and holo versions), Girly Bits I Hit My Bunny Phone, Girly Bits Belly Jeans (holo), KBShimmer Pigment of My Imagination, KBShimmer Myth You Lots (holo), Polish Me Silly Mesmerizing and Holy Shift (very similar), Enchanted Polish Time to Pretend (holo), Dance Legend Pulsar (scattered holo), Baroness X Karma, Baroness X Roy G. Biv (holo)
As far as opacity, The Ozotics (both 504 and 534) were definitely the sheerest and really benefit from being layered over a dark color (though I didn't do this in my comparison post to keep them all on an even playing field). All of the others built up really nicely on their own at 3 coats, and I honestly think you could do two coats of Darling Diva Polish Killer Queen and CrowsToes Muspelheim and be fine.
As you can see, I have a variety of finishes here so that definitely affects how vividly the pigment colors show up. The main base color you see is a blurple and then it has a shift to a pinky red. Of the two plain ones (Ozotic 504 and Dance Legend Celia), the colors are exactly the same but you can see that because of the increased opacity of Celia, the color is a bit more vibrant at 3 coats. If you layer 504 over a black base, the color pops just as much as Celia. CrowsToes Muspelheim also has a vivid coloring just like Celia and just has the added glitters in there. Of the 3 holos, you can see that Enchanted Polish Octopus Garden is decidedly more rich in coloring than either Ozotic 534 or Darling Diva Polish Killer Queen because the holo pigment is much more scattered and thus doesn't grey out the base color as much. I know it is hard to tell in these pictures, but Ozotic 534 and Darling Diva Polish Killer Queen do have the exact same color shifting pigment as the others, but you sacrifice the really rich colors of the pigment for the insane holo effect. The colors pop more in real life and even more if they are layered over a dark color, but nothing like the others that I'm showing you here; it's a much more subtle effect.
From the blurple, you see a dramatic reddish pink shift and then at extreme angles it goes to an orangey gold. Once again, you see the color shift most vividly in the non-ultra holo polishes, but you can still see a muted version of the color shift in Ozotic 534 and Darling Diva Polish Killer Queen. CrowsToes Muspelheim has even more fun going on because it has coordinating color shifting glitters in it as well.
And of course I wanted you to see a picture in the sunshine so you can see the ultra holos at work! Ozotic 534 and Darling Diva Killer Queen definitely have a crazy strong holographic effect while Enchanted Polish Octopus Garden's is more scattered. You can see here that Ozotic 534 has just slightly more color than DDP Killer Queen, and that is due to the density of the holo pigment in Killer Queen which makes it more opaque, but also slightly more washed out.
So do we have dupes? These polishes all have the same color shifting pigment in them, that's for sure, but their finishes affect their final look a LOT! I think that Celia is an excellent dupe and even better option than Ozotic 504 due to opacity. I also think that Darling Diva Polish Killer Queen is an excellent dupe of Ozotic 534 and, again, benefits from better opacity. I actually recognize that even a lot of the indie alternatives that I own aren't that easy to come by these days because they aren't stocked often or have been discontinued, but HAVE NO FEAR! If you just take a look at the massive list I have provided of polishes that use this same pigment, you will surely be able to fill the gap in your collection. I have personally heard a ton of great things about the offerings from KBShimmer, Girly Bits, and ILNP, so those would be at the top of my list for recommendations plus they all offer plain and holo polishes made with this pigment.