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

Optimization · Pure Optimization
A management game about ferrying spirits to the afterlife.

Optimization · Practiced Mastery
A deadpan janitor sim about mopping up the gory aftermath of sci-fi shooter battles.
Spiritfarer leans Optimization (Pure Optimization); Viscera Cleanup Detail leans Optimization (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Spiritfarer
Platforming is light and forgiving.
Viscera Cleanup Detail
Mop physics fumbling, lightly fiddly at most
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Spiritfarer
Spirits follow scripted arcs.
Viscera Cleanup Detail
Nothing opposes you
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Spiritfarer
Minor resource RNG.
Viscera Cleanup Detail
Messes are placed, not random in any meaningful way
Spiritfarer leans a little harder on optimization, though the gap is small.
Spiritfarer
Boat layout and crafting loops reward planning.
Viscera Cleanup Detail
Efficient cleanup order and bucket logistics are the game
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.