head to head
Neither is simply harder - they are hard in different places. DOOM (2016) demands more optimization; Slapshot: Rebound demands more reads.

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

Execution · Pure Mechanics
Physics hockey where manual stick control and outplaying humans decide everything.
DOOM (2016) leans Execution (Pure Mechanics); Slapshot: Rebound 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.
Slapshot: Rebound
Manual stick rotation makes every pass and shot a motor test
Slapshot: Rebound leans clearly harder on reads.
DOOM (2016)
Demons scripted attack patterns.
Slapshot: Rebound
Human defenders force constant deking and anticipation
Slapshot: Rebound leans a little harder on variance, though the gap is small.
DOOM (2016)
Minimal encounter randomness.
Slapshot: Rebound
Pure physics, explicitly no RNG by design
DOOM (2016) leans clearly harder on optimization.
DOOM (2016)
Rune and weapon mod picks meaningful.
Slapshot: Rebound
Team positioning and rotations matter but stay simple
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.