Beat mission 18 (Owaranai Ashita he EX) + use Kira (Zaft) 5 times That mission is an EX stage, and you don't need Kira (Zaft) to pilot Aile Strike. After clearing mission 18 just to go VS battle mode and set the time limit to 1 minute using Kira (Zaft) as your pilot 5 times.