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.

Variance · Systems & Chaos
A gothic exploration roguelike about sailing an underground ocean, trading terror for stories and profit.

Variance · Systems & Chaos
A gothic narrative exploration game about flying a steam locomotive through haunted skies.
Sunless Sea leans Variance (Systems & Chaos); Sunless Skies leans Variance (Systems & Chaos).
Sunless Skies leans a little harder on execution, though the gap is small.
Sunless Sea
Slow boat combat barely tests the hands
Sunless Skies
Slow locomotive combat asks little of the hands
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Sunless Sea
Horrors are scripted or random, never adaptive
Sunless Skies
Horrors and agents follow scripted storylets
Sunless Sea leans a little harder on variance, though the gap is small.
Sunless Sea
Hidden map, random events and unknown story branches dominate
Sunless Skies
Hidden ports, story branches and terror events
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Sunless Sea
Trade routes and fuel math converge once mapped
Sunless Skies
Trade routes and fuel economics are plannable
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.