I am Setsuna | Julienne's Legendary Spritnite: Eclipse

Go to Royburg with Julienne in your party. In the center of the city is Cornelius, speak to him. After a long conversation, head to the Last Lands. Go to the middle of the town and turn right until you walk in front of the second house. Approach the door and you will get the new info about the blacksmith.

Then, head to Archimell Ruins on the lower left of the main land. Enter the ruins and head to the second area. Head to the right, then west a bit and turn right to find another portal switch with a red light. The last time you came here, the switch is not responding. This time, it will respond when you call the blacksmith's name. Activate it and get ready for a boss battle with Grinche.

Grinche is a tough creature with slow ATB. You can fight him with two attackers and have another character who can do AoE healing. Be careful with his Stop magic, if your characters are affected by this magic, it's Game Over.

After Grinche is defeated, you will get Eclipse spritnite.