MerchSensei

Sanemi Shinazugawa's katana (Nichirin Blade) from Demon Slayer: Kimetsu no Yaiba is iconic for its forest green blade with a white jagged, wind-like hamon (hardening pattern), an interlocking 8-lobed star tsuba (handguard) mimicking a windmill, and a matching green scabbard adorned with white scarred markings.

Roronoa Zoro's Shusui from One Piece is a legendary Ō Wazamono grade "Black Sword" (Kokutō). It is recognizable by its distinct black blade with a red zig-zag hamon (hardening line), its flower-shaped golden/alloy tsuba (handguard), and a dark scabbard decorated with Wano Country style pink/red circular motif elements.

An LED Tanjiro Katana is a specialized light-up replica designed to simulate Tanjiro Kamado's iconic breathing techniques. These swords typically project a bright red glow to replicate Hinokami Kagura (Sun Breathing) or a striking white-to-blue glow representing his initial Water Breathing forms.

The Sword which has Mind of its own in One piece.