Hearthcliffe's Knife

Takumi Hearthcliffe's Knife (タクミ・ハースクリッフのナイフ) was a kitchen knife that Hearthcliffe transformed into a horcrux. It was the first horcrux he created, and was created from the killing of Hikari Uchida. The event took place in March 2000, with Hearthcliffe being eleven when he did this.

During a battle with Hearthcliffe at Minecraftia University in July 2005, Kumiko confiscated the knife from him after being disarmed by Shira's Master Blizzard and gave it to Driller, who then went on to destroy it using his hammer.

Creation of the Horcrux
When Hearthcliffe was in fifth grade, he murdered Hikari Uchida for revenge after confiscating his Game Boy the same day. After being familiar with horcruxes, he used her soul to turn the knife he used into his first horcrux.