Most modern PRFs come with an innate Slaying effect (Special cooldown -1) built into the base weapon before refinement. For a generic inheritable weapon, you have to sacrifice your A-slot or Sacred Seal to get that cooldown reduction. PRFs give you this for free, allowing you to stack Tempo, Special Spiral, or Time’s Pulse on top.
The term "PRF" originates from the game code, signifying a weapon that is locked to a specific unit or a very small group of related units (e.g., the Falchion sword wielded by various Marth descendants). Unlike iron, steel, or silver weapons that any sword user can equip, a PRF weapon is intrinsically tied to the character’s identity.
Key characteristics of a PRF Weapon:
Despite its power, PRF-based targeting has limits. The most famous is the Doppler notch: a target moving perpendicular to the radar’s line of sight (e.g., “beaming”) has zero relative velocity. To such a radar, that target looks exactly like stationary clutter. A skilled pilot can “notch” an incoming missile by turning 90 degrees.
Future weapons are mitigating this with:
In Fire Emblem Heroes, a PRF (often denoted by a flashing golden border around the weapon icon) is a weapon that only specific characters can wield. Think Falchion on Marth or Lucina, Raijinto on Ryoma, or Gleipnir on Eirika.
In mainline games, PRFs usually come with unique animations and high might. In FEH, they come with something much more potent: unique refine effects that often dictate an entire character’s playstyle.