head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is reads, and it is a single point.

Execution · Pure Mechanics
Routine shooter aim through scripted cartel firefights.

Execution · Pure Mechanics
Landmark FPS built on physics puzzles and tight gunplay.
Call of Juarez: The Cartel leans Execution (Pure Mechanics); Half-Life 2 leans Execution (Pure Mechanics).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Call of Juarez: The Cartel
Standard FPS gunfights run on aim alone
Half-Life 2
Gravity gun and shooting demand precision.
Call of Juarez: The Cartel leans a little harder on reads, though the gap is small.
Call of Juarez: The Cartel
Co-op secret objectives add mild teammate suspicion
Half-Life 2
Combine AI scripted, non-adaptive.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Call of Juarez: The Cartel
Enemy waves spawn identically each run
Half-Life 2
Almost no randomness.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Call of Juarez: The Cartel
Weapon levelling is a thin progression layer
Half-Life 2
Linear progression with no builds.
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.