Polyrhythm (ポリリズム Poririzumu?) is the 22nd minigame in Rhythm Tengoku. It features the Red Things that roll around and bounce on an assembly line. A sequel appears later on called Polyrhythm 2. Attaining a perfect gets the lyrics: Sweet Angel from Remix 3 for this game that you can read at the E-mail.
This game is structured on a grid with two pathways. Before the player starts, a rhythm is tapped out, using a bass drum to represent the lower path and a snare drum to represent the upper path. After this finishes, a rod will roll out , requiring the player to repeat the given pattern using the D-Pad for the top row and A button for the lower row. After the pattern is repeated, a new one is tapped out. The patterns sometimes vary between paths.
D-Pad: Bounce Rod (Upper Area)
A: Bounce Rod (Lower Area)
Hit: The rod bounces to the next block.
Barely: The rod bounces on. A barely counts as a miss.
Miss: The rod lands on the ground and explodes.
"工場長から" (From the factory head.)
"ちゃんと 運んでくれないとダメ。" (You must carry them properly.)
"左手が あそんでるヨ。" (Your left hand is playing around.)
"応用力を みにつけよう。" (Let's see your applied force.)
"まぁまぁ、 かな。" (OK, I guess?)
"よしと します。" (You did your best.)
"左手が しっかり仕事してるネ！" (Your left hand is working reliably!)
"リズミカルな 仕事ぶりだ！！" (A rhythmical working manner!)
"赤いモノ、量産は たいへんだなぁ…" (Red Thing mass production is quite difficult...)
"どんどん 赤いモノを 生産だ！" (Producing more Red Things!)
"赤いモノを 生産しまくりだネ！！" (Producing Red Things like mad!!)
This game appears to have inspired multiple aspects of Built to Scale in both Rhythm Heaven and Rhythm Heaven Fever, such as the general art design. Because of this, many fans consider this game to be a predecessor, referred to as "Built to Scale" in most fan translations.
The music from this game sounds a bit like the title theme from Rhythm Heaven Fever.