Alternate Builds Blacktron II Blacktron II Alternate Builds Instructions Added Large Alt Build Large Builds 6981 – Back C September 22, 2019November 3, 2021 Master Builder 2820 Views From: 6981: Aerial IntruderName: Mobile Intruder 1Instructions: View PDF | Download .io File Back C ContributionsName, PDF, and .io file submitted on October 31, 2021 by: IceAge2002