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 · Systems & Chaos
A visual novel thriller mixing escape-room puzzles with branching life-or-death story routes.

Optimization · Systems & Chaos
Deduction under permanent consequences - assembling hidden case facts into correct conclusions.
999: Nine Hours, Nine Persons, Nine Doors leans Optimization (Systems & Chaos); Lacuna leans Optimization (Systems & Chaos).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
999: Nine Hours, Nine Persons, Nine Doors
Tapping through text and puzzles, zero dexterity
Lacuna
Walking and dialogue choices need no dexterity
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
999: Nine Hours, Nine Persons, Nine Doors
Characters follow a fixed script, never adapt
Lacuna
Suspects follow a fixed script regardless of you
Lacuna leans a little harder on variance, though the gap is small.
999: Nine Hours, Nine Persons, Nine Doors
Hidden story branches and twists drive first playthroughs
Lacuna
The case is hidden information; wrong reads stick permanently
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
999: Nine Hours, Nine Persons, Nine Doors
Escape-room puzzles and route flowchart are fully solvable
Lacuna
Cross-referencing clues into correct deductions is the test
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.