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 · Pure Optimization
A first-person puzzle game where seeing the solution is the whole skill.

Optimization · Pure Optimization
An open-world sandbox solved through creative build optimization and routing.
Portal 2 leans Optimization (Pure Optimization); The Legend of Zelda: Tears of the Kingdom leans Optimization (Pure Optimization).
The Legend of Zelda: Tears of the Kingdom leans a little harder on execution, though the gap is small.
Portal 2
Portal placement requires some precision but timing is lenient.
The Legend of Zelda: Tears of the Kingdom
Combat and traversal need modest timing
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Portal 2
No opponent; puzzles are static.
The Legend of Zelda: Tears of the Kingdom
World is fixed, nothing adapts
The Legend of Zelda: Tears of the Kingdom leans a little harder on variance, though the gap is small.
Portal 2
Puzzles are deterministic with no randomness.
The Legend of Zelda: Tears of the Kingdom
Weapon durability adds light variance
Portal 2 leans a little harder on optimization, though the gap is small.
Portal 2
Solving the puzzle's logic IS the entire game.
The Legend of Zelda: Tears of the Kingdom
Build contraptions and route the open world
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.