head to head
Baldur's Gate II: Shadows of Amn asks more than Portal 2, and the gap is variance.

Optimization · Pure Optimization
The deepest optimization puzzle in the Infinity Engine lineage, rewarding encyclopedic knowledge of 2nd Edition AD&D systems.

Optimization · Pure Optimization
A first-person puzzle game where seeing the solution is the whole skill.
Baldur's Gate II: Shadows of Amn leans Optimization (Pure Optimization); Portal 2 leans Optimization (Pure Optimization).
Portal 2 leans a little harder on execution, though the gap is small.
Baldur's Gate II: Shadows of Amn
Pause-and-plan removes twitch entirely; micro-placement has marginal value
Portal 2
Portal placement requires some precision but timing is lenient.
Baldur's Gate II: Shadows of Amn leans a little harder on reads, though the gap is small.
Baldur's Gate II: Shadows of Amn
Enemies run scripted behaviour patterns, never modelling your tactics
Portal 2
No opponent; puzzles are static.
Baldur's Gate II: Shadows of Amn leans clearly harder on variance.
Baldur's Gate II: Shadows of Amn
Loot randomization and enemy ability use create hidden-information layers
Portal 2
Puzzles are deterministic with no randomness.
Baldur's Gate II: Shadows of Amn leans a little harder on optimization, though the gap is small.
Baldur's Gate II: Shadows of Amn
Mage spell sequences, dual-class builds and Spellhold routing define mastery
Portal 2
Solving the puzzle's logic IS the entire game.
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.