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 asymmetric horror FPS letting you play marine, alien, or predator, each with wholly different abilities.

Execution · Pure Mechanics
An action racer where players detonate the environment itself to wreck rivals and reroute the track.
Aliens versus Predator (1999) leans Execution (Pure Mechanics); Split/Second leans Execution (Pure Mechanics).
Split/Second leans a little harder on execution, though the gap is small.
Aliens versus Predator (1999)
Fast aliens and panicked aim demand twitch reflexes
Split/Second
Drafting, drifting and dodging collapsing set pieces.
Aliens versus Predator (1999) leans a little harder on reads, though the gap is small.
Aliens versus Predator (1999)
Asymmetric multiplayer pits unlike species against each other
Split/Second
Timing powerplays against human rivals rewards prediction.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Aliens versus Predator (1999)
Motion-tracker dread and dark vents hide enemy positions
Split/Second
Triggered explosions and route changes upend races constantly.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Aliens versus Predator (1999)
Mastering each species' tools and level knowledge
Split/Second
Knowing every trap and shortcut converges with play.
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.