head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is variance, and it is a single point.

Optimization · Pure Optimization
A slow-burn first-person adventure investigating strange scratching sounds in an isolated Victorian mansion.

Optimization · Pure Optimization
A mechanical journey adventure solved by understanding the logic of its automaton-filled world.
Scratches leans Optimization (Pure Optimization); Syberia leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Scratches
First-person point-and-click input is physically trivial
Syberia
Walking and clicking; zero reflex demand
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Scratches
No opponents at all, only an empty haunted estate
Syberia
NPCs follow scripted dialogue trees with no adaptive modelling
Scratches leans a little harder on variance, though the gap is small.
Scratches
The mystery's hidden answers drive a blind first run
Syberia
Linear journey with virtually no hidden-information surprises
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Scratches
Investigation puzzles resolve to one fixed solution path
Syberia
Mechanical clockwork puzzles require mapping part relationships
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.