Retinol — or as we in the beauty biz like to call it, liquid gold — is the purest form of vitamin A and beloved for its ability to even skin tone (especially hyperpigmentation-ravaged faces) and provide a boost of wrinkle-fighting collagen. This Asarai Sleepercell Retinol Serum ($45) is a great nonirritating option that specifically helps fight acne scarring. Just remember to use an SPF in conjunction with this serum, as all retinoids make your skin more sensitive to the sun.