The Golden Suit of Armor, contrary to its name, is not a piece of gear for Alphen or Kisara. It is much more useful than some silly clothing, though. The Golden Suit of Armor is an artifact that increases your EXP gain by a whopping 80 percent, which is an invaluable asset for late and post-game level grinding.
Leveling
The Golden Suit of Armor can be obtained by completing the Spirit Temple subquest. This quest becomes available in Traslida Highway at the same time that the The Wedge main quest unlocks, but we do not recommend that you attempt the quest at that moment.
While playing through, we found that you were likely to be around level 35 to 40 by the time the Spirit Temple subquest unlocks. The enemies you'll need to fight to finish the quest are all above level 60. We came back later and cleared the quest at around level 55, so it's certainly possible as early as then or even earlier, but the best option is to wait for level 60 before attempting this quest.
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Completing Spirit Temple
The quest has two parts to it: the dungeon and the boss. Every single enemy in this quest, boss included, is earth-element. Unlock some solid Wind Artes, craft some good Opal accessories, and you'll be sitting pretty.
The dungeon is counted as one giant combat sequence, making it unlike any other dungeon the player will have encountered before. This means that there's never a chance to fast-travel, level skills, gain EXP or SP, or even check a map. Keep fighting through the rooms of enemies to find the teleporters, and you'll eventually reach the boss. You'll be given a brief respite and a healing circle before the fight, so don't worry about conserving CP.
The boss itself, the Grand Gnome, is another instance of a boss you don't actually fight. It will summon a wave of enemies like you've been fighting, a gigant Zeugle, and a second wave of those enemies when the gigant Zeugle reaches half health. The Grand Gnome will fire lasers across the field periodically, but nothing more. Blast everything with some powerful Wind Artes and you should be fine.
After wiping out the Grand Gnome, head back to Traslida Highway, turn in the quest, and enjoy that sweet 80-percent extra EXP gain!
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