Thor #133 is one of the premier Silver Age Thor keys, featuring the first full appearance of Ego, the Living Planet, one of Marvel's most iconic cosmic characters. Created by the legendary team of Stan Lee and Jack Kirby, Ego remains one of Kirby's most imaginative creations and has enjoyed renewed popularity following his appearance in the Marvel Cinematic Universe. This copy has been professionally graded CGC 8.5 Cream to Off-White Pages, an impressive grade for a major Silver Age Marvel key. The striking Jack Kirby cover, depicting Thor confronting the sentient planet Ego, is considered one of the classic cosmic covers of the era and helped establish the increasingly ambitious scope of Marvel's universe during the mid-1960s. As one of the cornerstone issues in Thor's Silver Age run, Thor #133 enjoys consistent demand from collectors seeking significant first appearances, Jack Kirby masterpieces, and foundational Marvel cosmic keys. Copies in CGC 8.5 are scarce enough to command strong premiums while remaining attainable compared with the very highest grades. Professionally encapsulated by CGC, this book represents an outstanding investment-grade example of one of Marvel's most important Silver Age cosmic issues.