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 · Pure Optimization
Comedic point-and-click adventure of Guybrush Threepwood, hand-drawn at its peak.
999: Nine Hours, Nine Persons, Nine Doors leans Optimization (Systems & Chaos); The Curse of Monkey Island 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.
999: Nine Hours, Nine Persons, Nine Doors
Tapping through text and puzzles, zero dexterity
The Curse of Monkey Island
pointing and clicking only
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
The Curse of Monkey Island
no adaptive opponent
999: Nine Hours, Nine Persons, Nine Doors 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
The Curse of Monkey Island
puzzle solutions unknown on first play, then fixed
The Curse of Monkey Island leans a little harder on optimization, though the gap is small.
999: Nine Hours, Nine Persons, Nine Doors
Escape-room puzzles and route flowchart are fully solvable
The Curse of Monkey Island
inventory logic puzzles are fully solvable
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.