For those out there who are not fast enough to snag Formidable from the MAC Disney Venomous Villains Collection, you might be able to find a close dupe in Face Shop's BK901.
I happen to come across this possible dupe on my way to Lido with my deers for X-men first class and stopped by Face Shop at Wisma since we have some time before the movie starts.
You can imagine my excitement when i saw it and immediately Formidable came to my mind plus my BFF agreed with me that it is indeed a close dupe to Formidable.
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In the bottle, both looks very similar, but Face SHop's BK901 seems to have a tinge of Bluish tone to it whereas MAC's Formidable seems to lean more towards purple, both seems to sport the same kind of shimmer or glitter.
Application wise, BK901 requires 2 coats to attain the opaque effect while Formidable requires 3 coats, the consistency of the nail polish is thicker for BK901. Both dries up rather quickly, so there isn't much of a down time here.
When the nail polish coats dried iup completely, Formidable has a slightly rougher texture compared to BK901 and the difference in the sheen is a little more obvious. BK 901 has a slightly blue sheen whereas Formidable has a purpish sheen.
Nevertheless, both are very similar in my books
Size wise, there are no label stating the amount of ml BK901 contains but it shouldn't be much of a difference from Formidable.
In terms of pricing, BK901 is very much affordable at S$7.90 per bottle (much so since Face shop is having 20% off purchases more than S$10.00), Formidable retails at S$19.00 (but it is a limited edition, so expect to pay way much more if you were to get it from ebay).
In my personal opinion, BK901 is not a 100% dupe for Formidable but a close 80% cousin.
BK901: Priced at S$7.90, available at Face Shop (Wisma Atria).