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

Optimization · Practiced Mastery
A 3DS Kirby playing with foreground-background depth and the vacuum-everything Hypernova power.

Optimization · Practiced Mastery
A lovingly pixelled aerial adventure where Otus carries gunner friends through floating islands.
Kirby: Triple Deluxe leans Optimization (Practiced Mastery); Owlboy leans Optimization (Practiced Mastery).
Owlboy leans a little harder on execution, though the gap is small.
Kirby: Triple Deluxe
Easy main game, modest arena challenges
Owlboy
Flying and gunner-swapping in light combat
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby: Triple Deluxe
Bosses follow fixed patterns
Owlboy
Scripted pirates and bosses
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Kirby: Triple Deluxe
Levels fully deterministic
Owlboy
Hand-crafted, deterministic world
Owlboy leans a little harder on optimization, though the gap is small.
Kirby: Triple Deluxe
Sun-stone hunting and foreground-background gimmick puzzles
Owlboy
Boss patterns and secrets are learnable
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.