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 · Pure Mechanics
Push-forward arena FPS where movement and aim are the whole game.

Execution · Pure Mechanics
A loud, high-endurance test of accurate crowd control against relentless scripted enemy swarms in open arenas.
DOOM (2016) leans Execution (Pure Mechanics); Serious Sam: The First Encounter leans Execution (Pure Mechanics).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
DOOM (2016)
Aim, movement, glory-kill timing all peak.
Serious Sam: The First Encounter
Sustained accurate fire against enormous enemy hordes demands constant aim
DOOM (2016) leans a little harder on reads, though the gap is small.
DOOM (2016)
Demons scripted attack patterns.
Serious Sam: The First Encounter
All enemies are scripted and follow fixed rush patterns
Serious Sam: The First Encounter leans a little harder on variance, though the gap is small.
DOOM (2016)
Minimal encounter randomness.
Serious Sam: The First Encounter
Enemy placement is consistent across runs; no hidden information
DOOM (2016) leans a little harder on optimization, though the gap is small.
DOOM (2016)
Rune and weapon mod picks meaningful.
Serious Sam: The First Encounter
Enemy priority and positioning strategy are learnable but shallow
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.