So I just read this, the CEO added the below

    insts = [
      @ec2.instances.with_tag('Name', "CloudAMQP-#@name0*").to_a,
      @ec2.instances.with_tag('Name', "CloudAMQP-#@name-*").to_a,
      @ec2.instances.with_tag('Service', 'CloudAMQP').with_tag('Name', "#@name-*").to_a,
    ].flatten

unless they have a variable named "@name0" that first line would've evaluated to "CloudAMQP-*", which would then have the fun happen.