X-Men (Vol 1 1963) Issues 101-141

During issues 101-141 of The X-Men, Chris Claremont and artist Dave Cockrum continued their transformative work on the series, with significant contributions from writer/artist John Byrne and inker Terry Austin as the run progressed. This block of comics is heralded for some of the most iconic and defining storylines in X-Men history, including the dramatic "Phoenix Saga" and the "Dark Phoenix Saga," which deepened the characters and expanded the series' thematic complexity. The collaboration among these creators brought a new depth to the narrative and artistic quality of the series. Starting from issue #114, the title subtly began incorporating "Uncanny" into its cover design, setting the stage for the official title change with issue #142. This era not only solidified the series' place in comic book history but also set a high standard for storytelling within the superhero genre. Key issues include;

#101 - 1st appearance of Phoenix                            #102 - Origin of Storm. 1st Juggernaut vs Colossus
#104 - 1st cameo appearance of Starjammers         #107 - 1st appearance of Starjammers
#108 - John Byrne X-Men artwork run begins          #109 - 1st appearance of Weapon Alpha
#110 - Phoenix joins X-Men                                      #114 - 1st appearance of Uncanny in Title
#116 - Debut of Wolverines Healing Powers            #118 - 1st appearance of Mariko Yashida

#120 - 1st cameo appearance of Alpha Flight          #121 - 1st full appearance of Alpha Flight
#129 - Dark Phoenix Saga begins. 1st appearances of Kitty Pryde, Emma Frost, Sebastian Shaw, the Hellfire Club. 
#130 - 1st appearance of Dazzler                            #134 - Phoenix becomes Dark Phoenix
#137 - Death of Phoenix                                          #139 - Kitty Pryde joins the X-Men
#141 - Intro into Days of Future Past story, 1st appearances of new Brotherhood of Evil Mutants, Rachel (Phoenix II), Death of Franklin Richards