The Swordcatcher (剣薙ぎの薙刀 Ken nagi no naginata, lit. Sword Mowing Naginata) is a Naginata that is introduced in Fire Emblem Fates. Like its name suggests, the Swordcatcher is capable of inflicting effective damage against Sword and Katana-wielding enemies (3x its base weapon might); however, it is ineffective against non-sword or katana wielding enemies, dealing 4 less damage against them and suffering a -10 penalty to hit rate.
It can be considered as the 3DS series version of the Swordslayer.
Effective against swords; ineffective otherwise.
The naginata (薙刀), was a polearm used by samurai. It was essentially a spear with a curved blade. The naginata is one class of the Nihontō (日本刀), Japanese bladed weapons.