Complex sentence: Aragonés and Evanier eventually negotiated a deal with Marvel Comics (in their Epic imprint) for that company to take care of publication while preserving creator rights, and this resulted in the longest run of "Groo the Wanderer" with 120 issues.
Split into simpler sentences: Aragonés and Evanier eventually negotiated a deal with Epic Comics, an imprint of Marvel Comics, for that company to take care of publication while preserving creator rights. This resulted in the longest run of "Groo the Wanderer" with 120 issues.