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 · Pure Mechanics
An arcade beat 'em up testing crowd-control reflexes and memorised spawn patterns.

Execution · Pure Mechanics
Push-forward arena FPS where movement and aim are the whole game.
Alien Storm leans Execution (Pure Mechanics); DOOM (2016) leans Execution (Pure Mechanics).
DOOM (2016) leans a little harder on execution, though the gap is small.
Alien Storm
Arcade crowd control and dodge timing decide credits spent
DOOM (2016)
Aim, movement, glory-kill timing all peak.
DOOM (2016) leans a little harder on reads, though the gap is small.
Alien Storm
Alien waves follow fixed arcade scripts
DOOM (2016)
Demons scripted attack patterns.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Alien Storm
Enemy ambush spots are memorisable after one run
DOOM (2016)
Minimal encounter randomness.
DOOM (2016) leans a little harder on optimization, though the gap is small.
Alien Storm
Energy management and learned spawn patterns reward repetition
DOOM (2016)
Rune and weapon mod picks meaningful.
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.