head to head
The Bard's Tale IV asks more than Portal 2, and the gap is variance.

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

Optimization · Pure Optimization
A grid-based dungeon crawler about deep party building and environmental puzzles.
Portal 2 leans Optimization (Pure Optimization); The Bard's Tale IV leans Optimization (Pure Optimization).
Portal 2 leans a little harder on execution, though the gap is small.
Portal 2
Portal placement requires some precision but timing is lenient.
The Bard's Tale IV
grid-based combat needs little manual skill
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 Bard's Tale IV
scripted monster AI, no true adaptation
The Bard's Tale IV leans clearly harder on variance.
Portal 2
Puzzles are deterministic with no randomness.
The Bard's Tale IV
loot and encounter randomness
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 Bard's Tale IV
deep party build and puzzle-solving systems
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.