Prime Members: MuscleTech Mass Tech Extreme Mass Gainer Whey Protein Powder – Vanilla Milkshake, 22lbs (10kg) $21.37 after S&S

Seems like Amazon is price matching with the Vitamin Shoppe – must choose Amazon as the seller. Out of stock but can still order.
https://www.amazon.com/gp/product/B00LM4GABG