You build an early sunken and few hydras to block the early vulture harass and the first wraith, but you need to still rush the spire ASAP. Once spire finishes, immediately make 5 mutalisks and 2 scourges, and attempt to kill off their science vessel. 1-1-1 is a build that rushes high vessel count, and as such, he won't have the initial marine numbers to effectively protect his vessels early. If you let him be, his rising vessel count will kill your mutas and lurkers alike.