The Long Tomorrow
The Long Tomorrow is one of Moebius’ most significant works. Here is where he first delved into his future-city-as-vertical-sprawl motif, and it is this comic specifically that Ridley Scott used as his primary visual reference for Blade Runner. It was also written by Dan O’Bannon who, after Alejandro Jodorowsky’s adaptation of Dune collapsed, went on to write the script for Alien. He brought Moebius with him, who did costume design(particularly the space suits). O’Bannon, if I remember correctly, also wrote the first draft of Blade Runner.
Moebius would revisit his cities of unfathomable dystopian height when reteaming with Jodorowsky on The Incal. Many films have taken visual inspiration from this, most obviously Luc Besson’s The Fifth Element.