How do I unlock rank 4 parts for the Z Gundam?
Unlock and clear the “Zeta Activation” Extra Mission. To unlock the mission, you must clear Kamille’s Story Mode and get the special ending in the last stage (the one that plays if you keep Henken and Emma alive; btw, it’s fine to let Henken die, as long as you stop Emma from dying as well); you must also max out your relationship with Kamille and shoot down 3000 or more units while piloting the Z Gundam (combined total for all pilots).
