After arriving in the future, you seek a contract with Volt.
If you fight Bone Bows here, stay as far away as possible. Use Indignation on them.
Go north to find a Holy Bottle, then go through the nearby door to find chests that contain Lavender. Go back inside, and go left, and open the chests. The top one contains a Life Bottle and the bottom one contains a Shield Ring. Use the Shield Ring on anyone but Cless/Cress. The Shield Ring is a shield, NOT an accessory.
Go right twice, then up. Equip the Sorcerer's Ring and shoot the coil to open the door. Go through and open the chest (Grimorum), and equip the Grimorum on Klarth/Claus. Then follow the path.
Walk through the wall to the right and step on the gold switch, then go through the open door. Go up and right.
Outside, if you do NOT need an Orange Gummy, exit south, and skip to the next paragraph. Otherwise, go to the right and go up through the door. Keep going, and open the chest (Orange Gummy), but don't go through that door! Go back outside, and exit south.
Go into the room at the bottom right, hit the switch, then shoot the middle coil to open the door. Run through, then go to the right and down the stairs.
Open the chests. The left one contains an Apple, and the right one contains Bread. Then go to the next room. Make sure that you have Jet Boots equipped. Go up to the coils and shoot them, then run through the wall to the right where there is a dent in the wall, and go through the door. Go through the door on the right.
Go through the door above and hit the switch, then go to the right and go up to find a chest that contains a Sylph Broom. Equip it on Arche. Then exit straight down.
Go back through that thin wall, then go to the far left and go up to find another group of coils. First, hit the switch on the back wall, then use a Holy Bottle, shoot the coils, and run through the door that opened. Go through the first door.
Go to the far right of the room, shoot the third group of coils, then go left and shoot the second group of coils while the first is still on, then go left and shoot the first group while the others are still on, then go through the door.
When outside, make your party consist of Cless/Cress, Arche, Klarth/Claus, and Mint. Equip Klarth/Claus with a Mystical Rune and Holy Cloak. Get Klarth/Claus ready to summon Maxwell. Cancel Arche's Indignation and Ray, and get her ready to cast God Breath. If Cless/Cress has the Moon Falux equipped, switch to a non-elemental weapon.
Go north to fight Volt.
Stay away from the Arurouns, and have Cless/Cress attack and the others use the spells mentioned above.
After the battle, go back the way you came. Equip the ?Armor (Star Cloak) on anyone but Cless/Cress or Chester. Go to the room with the three sets of coils and use the teleporter on the right. Rest at Morrison's house, then go west and then north to the mountain pass. Go through the mountain pass, then go to Euclid, enter the northwest house, and talk to Stanley downstars. Afterward, you can travel the world.