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 · Practiced Mastery
Vehicular mayhem testing car handling plus knowing when wrecking beats racing.

Execution · Practiced Mastery
A stealth-action adventure testing cover shooting and memorised patrol routes.
Carmageddon II: Carpocalypse Now leans Execution (Practiced Mastery); Headhunter leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Carmageddon II: Carpocalypse Now
Perfect car control trivialises wrecking AI opponents and surviving
Headhunter
Cover shooting and bike license tests demand steady hands
Carmageddon II: Carpocalypse Now leans a little harder on reads, though the gap is small.
Carmageddon II: Carpocalypse Now
AI drivers follow set behaviours, never modelling the player
Headhunter
Enemy guards run fixed patrol scripts
Carmageddon II: Carpocalypse Now leans a little harder on variance, though the gap is small.
Carmageddon II: Carpocalypse Now
Pickup spawns and physics chaos add modest run-to-run noise
Headhunter
Level layouts hold few surprises after one pass
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Carmageddon II: Carpocalypse Now
Choosing wreck-versus-race strategy and upgrade economy is solvable
Headhunter
Learning patrols, routes and LEILA trials carries progress
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.