head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is variance, and it is a single point.

Execution · Pure Mechanics
Pioneering rhythm game where a rapping dog believes his way through button-cue raps.

Execution · Pure Mechanics
Pure rhythmic timing against fixed musical cues, minigame after minigame.
PaRappa the Rapper leans Execution (Pure Mechanics); Rhythm Heaven Megamix leans Execution (Pure Mechanics).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
PaRappa the Rapper
Hitting button cues on beat is the whole game
Rhythm Heaven Megamix
Beat-perfect input timing is the entire test
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
PaRappa the Rapper
No opponent; teachers follow set lines
Rhythm Heaven Megamix
No opponent - only the music
PaRappa the Rapper leans a little harder on variance, though the gap is small.
PaRappa the Rapper
Songs are fixed sequences
Rhythm Heaven Megamix
Every minigame plays identically each attempt
PaRappa the Rapper leans a little harder on optimization, though the gap is small.
PaRappa the Rapper
Freestyle scoring quirks for Cool rank
Rhythm Heaven Megamix
Cues are learned quickly; timing remains the wall
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.