X-Men Vol. 2 in 1991, Marvel launched X-Men, vol. 2 as a spinoff of the parent title Uncanny X-Men, with co-writers Chris Claremont and Jim Lee, previously the penciler on Uncanny, moving over to X-Men, while studio mate Whilce Portacio took over penciling duties on Uncanny. X-Men #1 is still the bestselling comic book of all time, with pre-order sales of over 8.1 million copies!