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

Optimization · Pure Optimization
An action RPG that crowns you king and tests your treasury more than your sword.

Optimization · Pure Optimization
Zelda-style puzzle dungeons and exploration with low-pressure combat.
Fable III leans Optimization (Pure Optimization); Star Fox Adventures 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.
Fable III
Simplified combat rarely punishes
Star Fox Adventures
Lock-on staff combat is deliberately forgiving
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Fable III
Scripted enemies
Star Fox Adventures
Dinosaurs and bosses are Rare-scripted patterns
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Fable III
Largely fixed world
Star Fox Adventures
Dinosaur Planet is fixed and explorable
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Fable III
Treasury management and kingdom promises drive the endgame
Star Fox Adventures
Zelda-style dungeon puzzles and item routing are the substance
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.