Webthe most notable effect of a bright red nichirin sword is its ability to hamper or even completely nullify a demon's regeneration.
The bright red nichirin sword also generates.
Webhow the sword breathing techniques work.
As you saw in this demon slayer sword guide, the katanas that most demon killers use in battle are crucial to them eliminating the foes.
White is the color associated with mist breathing, so it makes sense that muichiro tokito, the mist hashira, had it.
The attacks are based on swift movements.