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

Execution · Pure Mechanics
Spectacle hack-and-slash where reflexes and combo flow drive every fight.

Execution · Practiced Mastery
A classic arcade brawler sending the turtles through time to pummel Foot Clan waves.
God of War III leans Execution (Pure Mechanics); Teenage Mutant Ninja Turtles IV: Turtles in Time 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.
God of War III
Combo execution and QTE timing carry combat.
Teenage Mutant Ninja Turtles IV: Turtles in Time
Throw timing, positioning, and boss dodges are the whole test.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
God of War III
Bosses fully scripted spectacle.
Teenage Mutant Ninja Turtles IV: Turtles in Time
Foot Soldiers run fixed scripts.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
God of War III
Almost no randomness.
Teenage Mutant Ninja Turtles IV: Turtles in Time
Stages and waves are essentially fixed.
Teenage Mutant Ninja Turtles IV: Turtles in Time leans a little harder on optimization, though the gap is small.
God of War III
Upgrade paths short and obvious.
Teenage Mutant Ninja Turtles IV: Turtles in Time
Wave layouts and boss patterns are fully memorisable.
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.