Equip only to a "Ninja" monster. It gains 700 ATK. When this card is sent from the field to the Graveyard: Inflict 700 damage to your opponent.
Rulings
Netrep Rulings
If “Fuhma Shuriken” is equipped to “Chopman the Desperate Outlaw” by the effect of “Chopman the Desperate Outlaw”, “Fuhma Shuriken” is destroyed.
The damage from “Fuhma Shuriken” cannot be redirected by “Barrel Behind the Door”.
If the monster equipped with “Fuhma Shuriken” is sent to the Graveyard, the effect of “Fuhma Shuriken” will activate when “Fuhma Shuriken” is sent to the Graveyard.
The effect of “Fuhma Shuriken” activates regardless of whether it was equipped to a monster when it was sent to the Graveyard.