Lucas gave him a copy of Adventures of the Starkiller, Episode I: The Star Wars, and Cantwell set to work on the project. Lucas tasked Cantwell with designing several vehicles and ships including the X-Wing, Y-Wing, TIE/LN Fighter, Stardestroyer, Imperial Cruiser, Death Star, Landspeeder, Sandcrawler, Millennium Falcon, and T-16 Skyhopper. Cantwell started by sketching several drawings, based on brief conversations with George. He then took those designs and penciled concept art, which would be shown to studio executives along side Ralph McQuarrie's art. Cantwell created these colored-pencil works to lift George's spirit and enthusiasm for the project after being rejected by several studios.