I accidentally ordered three green shadows from Shiro. No complaints! But when I was looking at Snake it reminded me of a shadow I'd bought from Femme Fatale Cosmetics.
Snake "bright, lightly shimmery chartreuse"
Poison "vivid chartreuse green with soft yellow tones and a scattering of golden shimmer"
In the jar, Poison already looks like it's going to be a more yellow-toned chartreuse. Levels of shimmer are about equal in both eyeshadows.
Swatches done on bare, dry skin.
I'm not sure if it's just my skin, but Poison's apparent yellow tones make it a much darker chartreuse than Snake, which becomes almost a pastel yellow. I decided that a base might help the colour differences pull truer, so I turned to Nyx Jumbo Eye Pencil in Milk.
The addition of a white base proves it - whilst very similar applied, these shades aren't exact dupes. Poison is a bit darker and Snake is almost a pastel chartreuse. Eyeshadow junkies might want both, but you definitely don't need both in your collection - once on the eye, the differences would be negligible.
One more Shiro dupe battle to come!