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
Landmark FPS built on physics puzzles and tight gunplay.

Execution · Pure Mechanics
Reflex obstacle-dodging that converges to memorised lane choreography.
Half-Life 2 leans Execution (Pure Mechanics); Pepsiman leans Execution (Pure Mechanics).
Pepsiman leans a little harder on execution, though the gap is small.
Half-Life 2
Gravity gun and shooting demand precision.
Pepsiman
Reflex dodges in a fast auto-runner decide everything
Half-Life 2 leans a little harder on reads, though the gap is small.
Half-Life 2
Combine AI scripted, non-adaptive.
Pepsiman
No opponent; obstacles never adapt
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Half-Life 2
Almost no randomness.
Pepsiman
Obstacle layouts are fixed and quickly memorised
Pepsiman leans a little harder on optimization, though the gap is small.
Half-Life 2
Linear progression with no builds.
Pepsiman
Memorising obstacle sequences turns runs into rehearsal
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.