YSL Arlene's Nude (121) is a neutral mauve with a satin finish that is limited edition and retails for $38.00. In comparison, YSL Nude Antonym (17) is a warm mauve with a matte finish that is permanent and retails for $39.00.
YSL Nude Antonym (17) is 85% similar — it is warmer, less glossy.