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.

Execution · Pure Mechanics
Retro Studios' notoriously tough revival of Donkey Kong Country with relentless set-piece levels.

Execution · Pure Mechanics
Tests frame-tight jump timing through fully memorisable obstacle sequences.
Donkey Kong Country Returns leans Execution (Pure Mechanics); The Impossible Game leans Execution (Pure Mechanics).
The Impossible Game leans a little harder on execution, though the gap is small.
Donkey Kong Country Returns
Demanding rocket-barrel and mine-cart sections, strict timing
The Impossible Game
One mistimed jump restarts the level - perfect inputs win alone
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Donkey Kong Country Returns
Scripted hazards, no adaptation
The Impossible Game
Solo - nothing to predict
Donkey Kong Country Returns leans a little harder on variance, though the gap is small.
Donkey Kong Country Returns
Hidden puzzle pieces, fixed once found
The Impossible Game
Levels are identical on every attempt
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Donkey Kong Country Returns
KONG letters and time attack routes are learnable
The Impossible Game
Memorising the jump sequence is half the climb
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.