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

Execution · Practiced Mastery
Mid-demand 3D platforming execution across fixed gravity puzzles.

Execution · Practiced Mastery
Arcade brawler positioning and stamina against memorisable enemy waves.
Super Mario Galaxy leans Execution (Practiced Mastery); Teenage Mutant Ninja Turtles II: The Arcade Game 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.
Super Mario Galaxy
Gravity-bending jumps need timing, though forgiving by Mario standards
Teenage Mutant Ninja Turtles II: The Arcade Game
Crowd control timing and positioning under constant pressure
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Super Mario Galaxy
Bosses repeat fixed patterns - nothing adapts
Teenage Mutant Ninja Turtles II: The Arcade Game
Foot Clan waves are quarter-munching scripts
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Super Mario Galaxy
Galaxies are scripted; surprises evaporate after one visit
Teenage Mutant Ninja Turtles II: The Arcade Game
Spawns are fixed and memorisable
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Super Mario Galaxy
Star routes and comet challenges reward learned solutions
Teenage Mutant Ninja Turtles II: The Arcade Game
Learning safe spots and boss patterns is the progression
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.