Rarity is an aspect of all units appearing in Fire Emblem Heroes. It denotes both their, as the name suggests, rarity, and an approximation of how powerful the unit is. A unit's rarity is represented by a number of ★ on their stat screen and elsewhere during gameplay.
A unit's rarity, despite what its name may imply to some, is specific to individual units, and not every instance of the character. A unit's rarity can value from 1★ to up to 5★. A 5★ unit is going to be much more powerful than a 1★ unit at the same level, even if the two units are the same character.
The exact calculations for these statistical differences are currently unknown. Several characters also have specific skills that can only be unlocked once they meet the ★ requirement (often 5★) as well.
A character's rarity also alters several graphical elements, such as the border around their portrait. 5★ units will also have golden sparkles on their map icon and in their stat screen. 4★ units have silver sparkles in their stat screen, but not their map icon.
Generic enemies can also have rarity values. Generic enemies of higher rarity are seen in higher difficulties, and are more powerful than their less-rare brethren. The also have higher stats and more skills.
Rarity and summoning
The lowest possible rarity of characters obtained through summoning is 3★. 1★ and 2★ units are generally obtained from special maps that give out characters. Some characters can be summoned at any star amount between 3★ and 5★, and some characters, such as Lucina, can only be summoned as 5★, making them quite rare. Lower rarity versions of characters that can only be summoned as 5★ do appear as enemies on lower difficulties in the story mode.
A unit's rarity is shown immediately on the summoning screen under their map icon, making their rarity one of the first things known to the player. Aside from being stronger, units summoned at higher rarities also benefit from having more skills unlocked from the start. For example, s 3★ Henry will have Ruin, while a 4★ Henry will start with Rauðrraven, a more powerful spell.
Through a process known as Unlocking Potential, a character's rarity can be increased--for a cost. The character's rarity can be increased by one ★ once that character is level 20 or above. Once the character is at the required level the player can spend both Badges and Hero Feathers to unlock that character's potential. Upgrading a character from 1★ to 2★ is relatively trivial, though upgrading a character from 4★ to 5★ is quite expensive. When a character's rarity is upgraded their level is reset to level 1 and their stats are reduced to that of a level 1 unit, with the exception of SP and that unit's learned skills, which are retained. It is currently unknown if, for instance, taking a 1★ character to 5★ provides any particular bonuses.
The Badge used must match that unit's color. Red units use Scarlet Badges, blue units use Azure Badges, green units use Verdant Badges, and gray units use Transparent Badges.
|★ increase||Badges needed||Hero Feathers needed|
|1★ to 2★||/// 5||20|
|2★ to 3★||/// 10||200|
|3★ to 4★||/// 20||2000|
|4★ to 5★||/// 20||20000|
A 4★ Lilina, her rarity is shown above her title, Delightful Noble.
Sakura after having her potential unlocked.