They both share aldehydes, lots of Iso-E, and a contemporary/classic use of petitgrain/rosemary/oakmoss/musk.
Although they share so much, their attitudes are very different.
Fierce is warm and inviting, and Platinum Egoiste is extremely arrogant, aloof, and somewhat chilling.
I prefer Fierce of the two, and would add Curve to that list as well.
But the best scent of this style imo is Maitre's Garrigue.
I strongly suspect that the drydown of Maitre's Garrigue was the direct or indirect inspiration for all 3 aforementioned scents.http://www.basenotes.net/threads/224...atinum-Egoiste