The player uses the A Button to quickly unsheathe, slice, and re-sheathe their sword in order to cut down enemies moving to the beat of the music. Fog eventually creeps in to obscure the player's vision of the enemies and forces them to use their sense of rhythm to best them. The more times the samurai succeeds in felling his enemies, the more intense his stance and hairstyle become.
Hit: The samurai slices the enemy directly in half.
Barely: The samurai's sword smacks the enemy, causing it to tumble off the screen. His stance returns to the first one. A barely counts as a miss.
Miss: The enemy continues its path and hits the samurai, making him cry out in pain while flinging his entire body backward. His stance returns to the first one.
"見物人のはなし" (The spectator's talk)
"きほんが できてませんな。" (The basics are not down.)
"てきが見えないと ダメっぽい．．．" (Looks like it's no good when you can't see the enemy.)
"速いのが ニガテみたい．．．" (Looks like you're not good at the fast parts.)
"まぁまぁ、 かな。" (OK, I guess?)
"よしと します。" (You did your best.)
"てきが見えなくても イイカンジ！" (Even when you can't see the enemy, you did well!)
"速いテンポが うまくとれてる！" (You got the fast tempo well!)
"スローが おみごと！" (The slow parts were perfect!)
"刃こぼれしちまった！" (My blade is broken!)
"さらに精進（しょうじん）すべし！" (Must concentrate more!)
"切れあじ、 サイコーだ！！" (The feeling of a sharp blade is unbeatable!!)
The name of the game uses an old character (ゐ) that is rarely used in modern Japanese, where the game's name would be written いあい斬り, meaning "killing an opponent by drawing one's sword."
This game lacks an official English name due to Rhythm Tengoku not being released outside of Japan. The closest would be the name of Samurai Slice in Rhythm Heaven, which is named Iai Giri Gaiden in Japanese. However, it is still often called Samurai Slice by fans.
This is one of the few games that without a practice.