head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Execution · Practiced Mastery
Precision glaive throws against scripted enemies in a cover shooter frame.

Execution · Practiced Mastery
Dark-fantasy Doom-engine shooter trading shotguns for elven wands and tomes.
Dark Sector leans Execution (Practiced Mastery); Heretic 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.
Dark Sector
Glaive throws with manual curve control reward precise aim
Heretic
Classic FPS strafing and aim
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Dark Sector
Infected enemies follow fixed behaviour scripts
Heretic
Monsters follow fixed 90s AI
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Dark Sector
Encounters replay identically once learned
Heretic
Static level layouts
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Dark Sector
Power usage and upgrade choices reward planning
Heretic
Secret hunting, item hoarding, and route knowledge
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.