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
The console FPS landmark that introduced Master Chief and the ring world.

Execution · Practiced Mastery
N64 spy FPS famed for gadget-heavy missions and bot-filled multiplayer.
Halo: Combat Evolved leans Execution (Practiced Mastery); Perfect Dark 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.
Halo: Combat Evolved
Aim, grenade timing, and vehicle control
Perfect Dark
N64 manual aim and tight mission play
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Halo: Combat Evolved
Multiplayer duels reward reading humans
Perfect Dark
Multiplayer and clever sims add some human-style adaptation
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Halo: Combat Evolved
Covenant AI varies tactics slightly
Perfect Dark
Mission scripting fixed once learned
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Halo: Combat Evolved
Weapon sandbox knowledge and encounter routing
Perfect Dark
Objective routing on harder difficulty tiers
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.