Unlocking the Magic Key Doors
With the Magic Key in your possession, you can now head all over Erdrea unlocking the red doors that have been taunting you throughout your journey. It's also a good time to visit the remaining islands and knock out another two regions for Crossbow Targets. Below you'll find the suggested order in opening the doors and snagging the Crossbow Targets.
You don't have the ability to Zoom back to Cobblestone yet so Zoom to Gondolia - Sea and sail northeast to the island of Insula Australis. Head to the northwest of the island to find your first Magic Key Door, unlock it and open the chest to obtain a Slime Crown.
The Emerald Coast Crossbow Targets
From Insula Australis, make your way northeast a little and dock at the Emerald Coast. Begin by turning around from you current position to face the shack and spot the first Crossbow Target dangling from the roof. Rest at the Camp to add it to your Zoom list as you make your way north of it and into the corner. Turn to face the east here to spot the second Target. Continue east and under the tree towards the Door of Departure next, as the field opens up head along the western wall and then turn around to spot Crossbow Target #3 on the wall. Dash directly east of this location to find a small path leading down to an Ore gathering point containing two Silver Ores and a Gold Ore. Head back up the path and then south along the western edge to find a chest containing an Enchanted Stone. Finally, head on over to the Door of Departure and search behind it to find a Sparkly Spot containing a Green Eye.
Zoom back over to the Campsite here and then head directly west until you reach the last large tree, look up to find the fourth Crossbow Target. Travel northwest from here and after you cross the bridge, search in the northeast corner to find the last Crossbow Target. When you deliver your results to the Bodkin Bowyer at the Campsite you'll obtain four Seeds of Magic.
Grab a Horse from the Emerald Coast Campsite and then ride it back to the Village by way of Cobblestone Falls. Head southeast from the Hero's home and follow the edge down to the Magic Key Door, at the end of the path you'll find a chest containing a Wristorative. This useful accessory will restore +25 HP a turn when you rework it to +3.
While still in Cobblestone, exit to the Heliodor region to the north and make your way back into Heliodor. Use the stairs in the eastern corner of town to reach Downtown and then head down the street a little until you come to the Magic Key Door. Open it up and inside will be a chest containing 5000G.
Make your way to Hotto Steppe by way of Hotto next, head past the Campsite (using it to add it to your Zoom destinations if you don't already have it) and towards the Cryptic Crypt. Head west of the Ore gathering point here to find the Magic Key Door, unlock it and open the chest to obtain a Banishing Blade.
No lengthy traveling for this next door, Zoom over to Gallopolis and head to the Magic Key Door next to the Tavern on the east side. Inside you'll find three chests containing 2000G, Making the Magic Happen Recipe Book and a Seed of Skill. You'll also find lots of pots you can smash containing a Pretty Betsy and a Mini Medal.
Gondolia is up next, head over to where the Item shop is and you'll find the Magic Key Door next to it. Inside you'll find a chest containing a Divine Designs Recipe Book, a Seed of Magic and Dieamend in the barrels and another Mini Medal in the pot.
From the Campsite, head to the tower to the southwest and unlock the Magic Key Door. Inside here you'll find yet another three Mini Medals.
Zoom over to Puerto Valor next and head down to the Magic Key Door near the beach. Inside you'll find a chest containing a Falcon Knife Earring, a Dagger for Erik that will strike twice.
Lonalulu is next on your list, head all the way up the hill to the northeast of town to where the Canon Lady was positioned earlier and look to your right. Unlock the Magic Key Door and head inside, you'll find a chest with a Zombie Mail along with another Mini Medal and Seed of Life in the barrels.
L’Academie de Notre Maitre des Medailles
Return to the Acadamie next to find the Magic Key Door located to the northwest of the first floor. Inside you'll obtain a Thunderball and Uniforme de l'Academie from the chests and a Mini Medal and Seed of Skill from the pots. While you're here, hand over your medals to the Headmaster, you should be one off the next reward.
Return to Phnom Nonh next and take the stairs up to the top before heading around the southeast to find more stairs heading down the Magic Key Door. Inside you'll obtain the Secrets of the Silversmiths Recipe Book from the chest and a Sage's Elixir from the pots.
Zoom to The Strand and climb back aboard the Salty Stallion. Sail north of your location back to Insula Occidentalis and head to the north of the island to find the Magic Key Door. Inside you'll find a chest containing a Falcon Blade.
The final stop for now also houses the final Crossbow Target for the Insula Isles. Get back on the ship at Insula Occidentalis and begin sailing around the edge of Erdrea until you reach the Vortex of Light to the east of Insula Borealis (the island to the north). This will allow you to reach the last of the Insula Isles, Centralis.
Awarded for making port at every island on the sea.
Head east from the dock to the first tree where you can loot a hidden chest containing another Mini Medal (you can now grab the reward from the Academie when you have time). Head directly south from here to the beach where you'll discover a Sparkly Spot containing a Mirrorstone. Continue east along the southern edge to the next Sparkly Spot containing a Cherry Blossom Petal before heading into the northeast corner. Look up to the north here to discover the final Crossbow Target of the Insula Isles. Finally, open the Magic Key Door here and loot the chest to obtain a Sainted Soma.
Zoom back to The Strand and make your way back to Insula Occidentalis to the north to report your progress with the Crossbow Targets, you'll obtain four Pep Pips. Don't waste these as they'll come in handy later in the game when Levelling your party up. With all the Magic Key Doors open now, sail north from Insula Occidentalis into the frozen land in front you and disembark in Sniflheim.