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
Comic-panel beat 'em up notorious for punishing health drain and tough fights.

Execution · Pure Mechanics
Tests frame-tight jump timing through fully memorisable obstacle sequences.
Comix Zone 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.
Comix Zone
Brutal one-life brawling demands clean play
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.
Comix Zone
Enemies follow fixed attack scripts
The Impossible Game
Solo - nothing to predict
Comix Zone leans a little harder on variance, though the gap is small.
Comix Zone
Everything is placed and scripted
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.
Comix Zone
Panel routes and item use are memorizable
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.