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 · Practiced Mastery
A sci-fi shooter where aim and weapon-switching against scripted alien enemies is the core test.

Execution · Pure Mechanics
A top-down shooter testing aim and movement against relentless enemy hordes.
Halo: Combat Evolved Anniversary leans Execution (Practiced Mastery); Serious Sam's Bogus Detour leans Execution (Pure Mechanics).
Serious Sam's Bogus Detour leans a little harder on execution, though the gap is small.
Halo: Combat Evolved Anniversary
aim and grenade timing carry combat
Serious Sam's Bogus Detour
Top-down aiming and crowd-dodging are the lead
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Halo: Combat Evolved Anniversary
covenant AI is scripted, not adaptive
Serious Sam's Bogus Detour
Enemy hordes follow scripted rushes, not adaptive
Serious Sam's Bogus Detour leans a little harder on variance, though the gap is small.
Halo: Combat Evolved Anniversary
enemy spawns and drops vary
Serious Sam's Bogus Detour
Spawn timing and drops add some chaos
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Halo: Combat Evolved Anniversary
weapon sandbox and routes are solvable
Serious Sam's Bogus Detour
Weapon choice and arena positioning matter underneath
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.