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
Gothic PS1 action horror of brutal melee against Victorian monsters.

Execution · Practiced Mastery
A campy 16-bit run-and-gun about rescuing neighbors from B-movie monsters.
Nightmare Creatures leans Execution (Practiced Mastery); Zombies Ate My Neighbors 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.
Nightmare Creatures
Combo timing and dodges against tough monsters
Zombies Ate My Neighbors
Dodging monsters while sniping with squirt guns
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Nightmare Creatures
Creatures use fixed attack patterns
Zombies Ate My Neighbors
Monster movie AI is fully patterned
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Nightmare Creatures
Ambush placement unknown first time through
Zombies Ate My Neighbors
Victim placement varies slightly per level
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Nightmare Creatures
Adrenaline meter management and route learning
Zombies Ate My Neighbors
Weapon-versus-monster matchups and level routing
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.