X-Men vol 4, Roy Thomas was starting out as a writer and boy, this guy filled the panels with thousands of words. Reading it felt more like a chore. Plus Werner Roth's art is so so, he drew a beatiful Jean Grey, but when it comes to action scenes he lacked the raw and power that a Jack Kirby or even a Romita provided to their mags. I think there are also some Don Heck issues that are very mediocre.