Collects Avengers (1963) #41-50 and Avengers Annual (1967) #1.
*Earth's Mightiest Heroes gain one of Earth's Mightiest artists: the one and only John Buscema! Big John joins Roy Thomas for the beginning of their classic Avengers collaboration. And here's what they have in store for you: Hercules goes mano-a-mano with the Dragon Man, Captain America mixes it up with the Russian Red Guardian, the Avengers battle the Super-Adaptoid, Goliath and the Wasp fight the Whirlwind, and a hero redeems the role of the Black Knight - only for Quicksilver and the Scarlet Witch to defect to Magneto and the Brotherhood of Evil Mutants! And topping it off, Avengers past and present join together against the Mandarin and his cadre of villains in the first ever Avengers Annual!
*Source: marvel.com