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

Optimization · Practiced Mastery
A block-stacking puzzle about building paths to collect items.

Optimization · Practiced Mastery
Open-world Hyrule built on physics puzzles and exploration over reflex tests.
Hello Kitty's Cube Frenzy leans Optimization (Practiced Mastery); The Legend of Zelda: Breath of the Wild leans Optimization (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Hello Kitty's Cube Frenzy
Block placement timing needs light dexterity
The Legend of Zelda: Breath of the Wild
Parry timing and aiming matter but forgiving.
The Legend of Zelda: Breath of the Wild leans a little harder on reads, though the gap is small.
Hello Kitty's Cube Frenzy
Solo with no opponent to predict
The Legend of Zelda: Breath of the Wild
Enemies follow fixed scripted behaviors.
Hello Kitty's Cube Frenzy leans a little harder on variance, though the gap is small.
Hello Kitty's Cube Frenzy
Falling block colors add some randomness
The Legend of Zelda: Breath of the Wild
Weapon drops and weather lightly randomized.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Hello Kitty's Cube Frenzy
Planning staircases and color matches solves levels
The Legend of Zelda: Breath of the Wild
Shrines, cooking, traversal routes fully solvable.
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.