Oh, i thought i included that. Opps! I'm barely NC15. My main problem is that my lips are super pigmented and the nudes that works for my skintone.. tends to not show up. Similar to what Pure zen did. Sigh. such a pretty shade too. I have been eyeing Lady gaga 2!

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Thank you.
I'm NC15 with red lips too. What you might need is something with yellow, peach or even grey undertones to cancel out your natural lip color, while still complimenting your skin tone. The ones that look really odd in the tube often wind up being the most flattering on me. If you get just the right canceling color, you can go for a sheerer texture and still have it read nude, but more opaque textures are fine if you pat them into your lips, instead of applying them heavily. The warmth of your fingers will blend the lipstick in with your skin nicely that way.
In the winter, the very best nude I've got is Restrict. That one is just perfect and very romantic. In the spring, I had the best luck with Playing Koi, and that was a color that didn't work for a lot of people - it's very pale salmon/peach. For summer, I enjoyed Salute! this year - it's like a little more warmed up Playing Koi. These were all limited though, but Salute! might still be around here and there. One that IS around that is absolutely gorgeous in the more beige nude department, rather than pale nude is
Cusp of Dawn. You should check that one out since it should still be available - it's got a beautiful, soft, semi-sheer texture too. I looooooove it!
Nudes are tricky to match, so just be choosey and try a bunch of them in person - you'll know which one is working when you see it. There wasn't a single nude in the recent cremesheen+pearl collection i liked, and all the nudes from Naturally were awful on me too. I haven't had a perm MAC nude lipstick that was really great for me either, unless you want to count Sheer Mandarin Sheen Supreme, which is very yellow apricot, but turns a soft nude on me when I apply it lightly. It will just click when it's right.....like love!