head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Execution · Practiced Mastery
The NES classic that introduced Kirby's copy abilities across a colourful, secret-stuffed Dream Land.

Execution · Practiced Mastery
A monochrome puzzle-platformer about a boy lost in limbo.
Kirby's Adventure leans Execution (Practiced Mastery); Limbo leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby's Adventure
Easy platforming with optional tougher secrets
Limbo
Tight platforming with trial-and-error.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby's Adventure
Scripted enemies and bosses only
Limbo
Hazards are scripted.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby's Adventure
Hidden switches found once, known forever
Limbo
No randomness.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby's Adventure
Copy ability choice and secret routes
Limbo
Puzzles have fixed solutions.
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.