While Mitsuri Kanroji's base attacks are more than enough to take out most demons, the most powerful attacks in her arsenal are the five "Forms" of Love Breathing she has mastered.
Thus far, we know Love Breathing has six different Forms that can be used during battle, though we've only seen five of them in the anime. When using "First Form: Shivers of First Love," Kanroji rushes forward and delivers multiple strikes with one swing that "shivers" while passing through the target. "Second Form: Love Pangs" is once again a single swing that contorts Kanroji's whiplike sword to slice the target from multiple angles at once.
"Third Form: Catlove Shower" forces Kanroji to jump into the air and deliver a cascade of arcing slashes in the empty air below her, which explode into pink and green sparks after the fact. "Fifth Form: Swaying Love, Wildclaw" is an attack where Kanroji backflips into the air and then rockets back towards the ground, spinning her sword to create a pink tornado of slashes on the way down. "
"Sixth Form: Cat-Legged Winds of Love" seems like just a simple downward slash in the anime but actually has a different effect in the manga, where the true power of the Sixth Form is that it allows Kanroji to whip and retract her sword at lightning speed to create a volley of constant overhead slashes. In any case, it will certainly be interesting to see if Kanroji uses the full power of the Sixth Form in Season 4 — and if we'll ever see the mysterious Fourth Form of Love Breathing, which has never been revealed in either the "Demon Slayer" anime or manga.