Brave weapons (also known as Hero Weapons) are weapons specifically designed to give the wielder an advantage in combat, allowing the user to always attack more than once, regardless of attack speed. They usually require a B-rank or higher to wield. In Fire Emblem Awakening and Fire Emblem Fates, they require an A-rank to wield.
For example, if the user of the Brave weapon is faster than the opponent, the Brave weapon user will strike 4 times instead of 2; the user will attack twice before the enemy counter-attack, then attack twice more after the enemy counter-attack. However, if the Brave weapon user is not faster than the opponent, the user will only strike 2 times instead of 1; the user will attack twice (before the enemy counter-attack) and no more. If, however, the enemy is also wielding a Brave weapon, the same rules apply for them (e.g. Player attacks twice, enemy attacks twice, player attacks twice more, etc.)
The main drawback of Brave weapons is that they wear out and subsequently break much quicker than regular weapons (because of their double usage each turn), and usually have a very high weight. In the GBA games, they have 30 durability and their Might is the equivalent of a Steel sword. In Fire Emblem: Radiant Dawn, they have 40 durability, but their previous stats remain unchanged. Also, the extra attacks will not count towards Weapon EXP. The best strategy is to save the Brave weapons for the final chapter or strong bosses.
In Radiant Dawn, the blessed sword Amiti (used exclusively by Queen Elincia) could also be considered a Brave weapon (although it is significantly more powerful and accurate, gives +3 Defense and Resistance and has infinite uses). In Thracia 776, the magic tome Dime-Thunder could be considered a Brave weapon with its ability to strike twice automatically.
In Fire Emblem: Shadow Dragon, Brave weapons can only be obtained from the Online Shop on either Saturday or Sunday, and only three of each Brave weapon type can be purchased per save file. The ability to forge Brave weapons in this game makes them the most powerful regular weapon the player can obtain. This trait sees Brave weapons used heavily on WiFi battles.
In Fire Emblem Fates, Brave weapons make a return again, and like in Awakening, require an A Rank in the respective weapon to use. Only Conquest players can buy them from a level 3 Nohrian Armory, and even then, only one is in stock. The only way to get more of them is through the DLC Museum Melee, and a few appear in chests on specific playthroughs. Unlike the previous installments, Brave weapons can only double attack during the player's turn (4x if they have 5+ speed then the enemy).
This time, the Brave weapons come with different drawbacks; the brave sword, lance and axe drop the user's defense and resistance by 4. The Brave Bow is renamed the Crescent Bow and drops the user's strength by half after battle, which is restored by attacking again. There are also a few other weapons that function like a Brave weapon; such examples include Lightning (which drops Magic and Skill by 2 after attacking), the Soldier's Knife and Snake Spirit (which drops strength/magic by half after battle).