I've been meaning to do this post for ages, as I've accumulated requests for the last month or two. Anyways, finally it's here!
Top to bottom we have Lynnderella Chocolotta Love over a white base, Ozotic 505 over black (which makes the colour shift look incredible!), Picture Polish Mask-a-rade over black, and Up Colors Beijo na Boca also over black.
On the thumb you can see Nails Inc Cheyne Walk over black, which doesn't really discernibly change the look of it so much; with one more coat it would look the exact same as it would without any base colour.
I hope these layering swatches were helpful for you! Out of these, I think Ozotic 505 and Picture Polish Mask-a-rade benefit the most from being layered over black- it really brings out the colour shift.