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

Execution · Practiced Mastery
An open-city sequel deepening freeflow combat and predator gadget play.

Execution · Practiced Mastery
A movie tie-in testing combo timing against scripted duels.
Batman: Arkham City leans Execution (Practiced Mastery); Star Wars: Episode III - Revenge of the Sith leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Batman: Arkham City
Combo chains and counters need timing.
Star Wars: Episode III - Revenge of the Sith
Lightsaber combos and blocks need modest timing
Star Wars: Episode III - Revenge of the Sith leans a little harder on reads, though the gap is small.
Batman: Arkham City
Enemies scripted, not adaptive.
Star Wars: Episode III - Revenge of the Sith
Versus duel mode adds light human prediction
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Batman: Arkham City
Fixed encounters and challenges.
Star Wars: Episode III - Revenge of the Sith
Encounters are fixed movie-scripted setpieces
Batman: Arkham City leans a little harder on optimization, though the gap is small.
Batman: Arkham City
Gadget combos and challenge maps learnable.
Star Wars: Episode III - Revenge of the Sith
Combo unlocks and boss patterns are quickly mapped
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.