Effective Against
KitsuneSome creatures — the kitsune being the primary example — can be killed by a straightforward stab to the heart with any weapon. No special material is required; the location of the wound is what matters. This is one of the simpler kill methods in the bestiary but requires precise aim and the ability to get within arm's reach of a creature that is typically faster and stronger than a human.
Effective Against
The kitsune is killed by a heart stab with any blade. Some other creatures are also vulnerable to heart-targeted attacks, though many require a specific material (silver to the heart for werewolves, for instance). The distinction is important: for a kitsune, a standard steel knife through the heart is sufficient. For a werewolf, only silver to the heart works.