You were in Neo Arcadia, where its government was holding a full-blown Reploid attack against the resistance, the group you were aiding. While fighting, you were almost taken out by a Pantheon Guardian, before it was slashed in half by Zero, who was sporting a new look.

“I’m glad that you’re alright. We can’t have any of our allies fall!” He then uses his Z-Saber to slash more enemy reploids that were coming your way.