head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Optimization · Light / Casual
A darkly satirical toy-burning game about feeding an endless fireplace.

Optimization · Light / Casual
A whimsical fantasy point-and-click adventure full of puzzle-solving humor.
Little Inferno leans Optimization (Light / Casual); The Book of Unwritten Tales 2 leans Optimization (Light / Casual).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Little Inferno
Drag items into a fire, that's it
The Book of Unwritten Tales 2
no physical skill, point-and-click
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Little Inferno
No opposition
The Book of Unwritten Tales 2
no adversarial adaptive opponent
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Little Inferno
Combo names hint at discoverable pairings
The Book of Unwritten Tales 2
negligible randomness
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Little Inferno
Finding burn combos is a light solvable layer
The Book of Unwritten Tales 2
inventory-puzzle logic to solve
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.