Seals will be required if you want to take Certification Exams.
To complete certification exams and change character classes you’ll need to get seals in Fire Emblem Three Houses. There are numerous types of Seals in the game, and you’ll need to do different things to get the different types of Seals. Upgrading your characters to beginner classes you’ll need Beginner Seals, for Intermediate Classes you’ll need Intermediate Seals, and for Advanced Seals for Advanced Classes. Towards the end-game you’ll eventually need even more valuable Seals called Master Seals and unique seals like the Dark Seal for Dark Magic classes.
Beginner and Intermediate Seals
The Beginner and Intermediate Seals will be pretty easy to come by in missions in the early goings of Fire Emblem Three Houses. These seals will drop by completing missions and they can also be purchased in the Marketplace for 500 and 1000 Gold Respectively.
Advanced Seals
Advanced Seals can also be purchased in the Marketplace for 1000 Gold. Advanced Seals will also drop from missions.
Master Seals
Master Seals can be purchased in the original item shop, but a second items shop will open in Act which will have a better supply of Master Seals to upgrade characters.
Dark Seals
There are a couple of different opportunities to get the Dark Seal which is used to create a Dark Magic character. Your chances to get the Dark Seal will be when you encounter the Dark Knight. The Seal can be stolen from the Dark Knight with the right class, or it can be earned if you defeat the Death Knight. You’ll first encounter the Death Knight when you play the mission Assault at the Rite of Rebirth. While it’s recommended to steer clear of this enemy when you first encounter him, beating him will reward you with this powerful item.
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Attack of the Fanboy / GAME GUIDES / Fire Emblem Three Houses How to Get Seals