As with past games in the Fire Emblem series, people can use a Second Seal or Master Seal to change a character’s class in Fire Emblem Engage. However, you don’t have immediate access to either item. Rather, you need to buy or earn them. They are limited stock items in the Somniel initially, though both occasionally show up in chests or after beating opponents in a map.
You’ll find your first Master Seal as an incidental reward. For example, you can get one in a locked chest in early maps. However, eventually the Somniel’s Item Shop will carry them. For 2,500G, you can get one. These are limited items initially, so you won’t be able to get enough for everyone right away. As long as a character hit level 10 in a class, you can promote them with a Master Seal. By chapter 9, you will start seeing them in the store after major chapter battles. Once you beat Fire Emblem Engage, an unlimited supply will be available in the Item Shop.
As for the Second Seal you can use to change your class, it is also available in Anisse’s Item Shop in Fire Emblem Engage around the same time the Master Seal appears in the store. Again, it is a limited item. One costs 2,500G. Using it allows someone to change a character’s class to another one on the equivalent tier. You don’t need to hit a level requirement in a class to use it. Like the Master Seal, unlimited numbers of Second Seals will be sold after you beat the game.
However, having a Master Seal or Second Seal isn’t the only requirement for changing classes. You also need to meet certain weapon proficiency requirements. For example, if Diamant’s axe proficiency is at B or higher, a Second Seal would let him change from his Lord base class to a Axe Fighter or Axe Armor. However, for him to change to his Lord advance class, he must be at least at level 10 and have S-level sword proficiency and A-level axe proficiency.
By the time you reach the end of Fire Emblem Engage, an infinite number of Second Seals and Master Seals will be available. However, until the endgame, they are doled out sparingly.
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